Isn’t this your employer’s problem? From your description, it sounds like you’ve collectively isolated Lutz from causing problems for you guys. Has your supervisor asked your opinion?

If you’re looking to make a game, focus on game engines. There’s a bunch to choose from, but there’s 2 main ones: Unreal and Unity. Of the two, I’d say Unity is more beginner-friendly, with tons of resources and a huge community. You can use Unity to build anything from 2d sides scrollers on the web to full-blown networked FPS games running on consoles.