Add it to your server
In your server's .ini file (servertest.ini by default), add these to the existing WorkshopItems= and Mods= lines, separated by a semicolon (;).
WorkshopItems=3819089720
Mods=ZombieBossB42
| Workshop item | Subscribers | Declared in |
|---|---|---|
| ZombieBoss3819089720 | 3 | description footer |