I started my mineos.service once without the symlink and once with it, but the results seem to be the same.
mineos.log:
{"level":"info","message":"Starting up server, using commit: b68925b fixed issue with mineos_console.js requiring servername for -V\n","timestamp":"2018-07-04T13:34:09.963Z"}
{"date":"Wed Jul 04 2018 15:34:27 GMT+0200 (Central European Summer Time)","process":{"pid":1269,"uid":0,"gid":0,"cwd":"/","execPath":"/usr/bin/node","version":"v10.5.0","argv":["/usr/bin/node","/mnt/raid/gameserver/minecraft/webui.js","start"],"memoryUsage":{"rss":66371584,"heapTotal":24412160,"heapUsed":16205960,"external":943309}},"os":{"loadavg":[0.04296875,0.025390625,0.001953125],"uptime":22787},"trace":[{"column":15,"file":"internal/modules/cjs/loader.js","function":"Module._resolveFilename","line":594,"method":"_resolveFilename","native":false},{"column":25,"file":"internal/modules/cjs/loader.js","function":"Module._load","line":520,"method":"_load","native":false},{"column":17,"file":"internal/modules/cjs/loader.js","function":"Module.require","line":650,"method":"require","native":false},{"column":18,"file":"internal/modules/cjs/helpers.js","function":"require","line":20,"method":null,"native":false},{"column":19,"file":"/mnt/raid/gameserver/minecraft/node_modules/userid/lib/userid.js","function":null,"line":5,"method":null,"native":false},{"column":30,"file":"internal/modules/cjs/loader.js","function":"Module._compile","line":702,"method":"_compile","native":false},{"column":10,"file":"internal/modules/cjs/loader.js","function":"Module._extensions..js","line":713,"method":".js","native":false},{"column":32,"file":"internal/modules/cjs/loader.js","function":"Module.load","line":612,"method":"load","native":false},{"column":12,"file":"internal/modules/cjs/loader.js","function":"tryModuleLoad","line":551,"method":null,"native":false},{"column":3,"file":"internal/modules/cjs/loader.js","function":"Module._load","line":543,"method":"_load","native":false}],"stack":["Error: Cannot find module '/mnt/raid/gameserver/minecraft/node_modules/userid/build/Debug/userid.node'"," at Function.Module._resolveFilename (internal/modules/cjs/loader.js:594:15)"," at Function.Module._load (internal/modules/cjs/loader.js:520:25)"," at Module.require (internal/modules/cjs/loader.js:650:17)"," at require (internal/modules/cjs/helpers.js:20:18)"," at Object.<anonymous> (/mnt/raid/gameserver/minecraft/node_modules/userid/lib/userid.js:5:19)"," at Module._compile (internal/modules/cjs/loader.js:702:30)"," at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)"," at Module.load (internal/modules/cjs/loader.js:612:32)"," at tryModuleLoad (internal/modules/cjs/loader.js:551:12)"," at Function.Module._load (internal/modules/cjs/loader.js:543:3)"],"level":"error","message":"uncaughtException: Cannot find module '/mnt/raid/gameserver/minecraft/node_modules/userid/build/Debug/userid.node'","timestamp":"2018-07-04T13:34:27.064Z"}
{"level":"info","message":"Starting up server, using commit: b68925b fixed issue with mineos_console.js requiring servername for -V\n","timestamp":"2018-07-04T13:34:27.723Z"}
{"level":"info","message":"Starting up server, using commit: b68925b fixed issue with mineos_console.js requiring servername for -V\n","timestamp":"2018-07-04T13:35:27.324Z"}
{"date":"Wed Jul 04 2018 15:36:11 GMT+0200 (Central European Summer Time)","process":{"pid":1331,"uid":0,"gid":0,"cwd":"/","execPath":"/usr/bin/node","version":"v10.5.0","argv":["/usr/bin/node","/mnt/raid/gameserver/minecraft/webui.js","start"],"memoryUsage":{"rss":61227008,"heapTotal":22839296,"heapUsed":16247488,"external":1302752}},"os":{"loadavg":[0.0048828125,0.01513671875,0],"uptime":22891},"trace":[{"column":15,"file":"internal/modules/cjs/loader.js","function":"Module._resolveFilename","line":594,"method":"_resolveFilename","native":false},{"column":25,"file":"internal/modules/cjs/loader.js","function":"Module._load","line":520,"method":"_load","native":false},{"column":17,"file":"internal/modules/cjs/loader.js","function":"Module.require","line":650,"method":"require","native":false},{"column":18,"file":"internal/modules/cjs/helpers.js","function":"require","line":20,"method":null,"native":false},{"column":19,"file":"/mnt/raid/gameserver/minecraft/node_modules/userid/lib/userid.js","function":null,"line":5,"method":null,"native":false},{"column":30,"file":"internal/modules/cjs/loader.js","function":"Module._compile","line":702,"method":"_compile","native":false},{"column":10,"file":"internal/modules/cjs/loader.js","function":"Module._extensions..js","line":713,"method":".js","native":false},{"column":32,"file":"internal/modules/cjs/loader.js","function":"Module.load","line":612,"method":"load","native":false},{"column":12,"file":"internal/modules/cjs/loader.js","function":"tryModuleLoad","line":551,"method":null,"native":false},{"column":3,"file":"internal/modules/cjs/loader.js","function":"Module._load","line":543,"method":"_load","native":false}],"stack":["Error: Cannot find module '/mnt/raid/gameserver/minecraft/node_modules/userid/build/Debug/userid.node'"," at Function.Module._resolveFilename (internal/modules/cjs/loader.js:594:15)"," at Function.Module._load (internal/modules/cjs/loader.js:520:25)"," at Module.require (internal/modules/cjs/loader.js:650:17)"," at require (internal/modules/cjs/helpers.js:20:18)"," at Object.<anonymous> (/mnt/raid/gameserver/minecraft/node_modules/userid/lib/userid.js:5:19)"," at Module._compile (internal/modules/cjs/loader.js:702:30)"," at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)"," at Module.load (internal/modules/cjs/loader.js:612:32)"," at tryModuleLoad (internal/modules/cjs/loader.js:551:12)"," at Function.Module._load (internal/modules/cjs/loader.js:543:3)"],"level":"error","message":"uncaughtException: Cannot find module '/mnt/raid/gameserver/minecraft/node_modules/userid/build/Debug/userid.node'","timestamp":"2018-07-04T13:36:11.706Z"}
{"level":"info","message":"Starting up server, using commit: b68925b fixed issue with mineos_console.js requiring servername for -V\n","timestamp":"2018-07-04T13:36:12.216Z"}
the dirrctory /usr/games still does not exist.