Black screen when applying patch

[Auspiciius]

My buddy and I applied the same assembly patch and joined a custom multiplayer lobby with anti-cheat disabled. The person who hosted could load in and play with the mod. The person who joined the hot got a black screen and would not load into the game. This worked both ways so we both had the patch installed correctly I would assume.

To Reproduce
Have any two people apply the same patch and be in the same multiplayer lobby with the patch. Launch the game and cry.

Expected behavior
I expected the game to load and both players to play with the mod working.

Screenshots
Not really applicable. A black screen is pretty self explanatory.

PC (please complete the following information):

• OS: Windows 10 (both users)

Additional context
This was a custom patch that I created which turned the assault rifle into a laser beam cannon.