What the official listing confirms
Steam identifies the game as a one-to-four-player co-op simulator.
Use this as a controlled first-session test
Record host, guest, build and exact error text for a reproducible connection test.
- Match game builds
- Host a private session
- Invite one player
- Add the remaining group
- Record join failures
Keep the answer current
Roadside Research can change after updates. Verify patch-sensitive values in the current build and record the date before treating a route, build, or requirement as permanent.
Local tracker