I think it's cool to see this game revived but I also think it's kinda wrong to recreate a game that's not technically dead and plan on asking money to help before talking to the creator. Assuming you get that all situated though, I think a different engine would be better, especially if you're planning on adding more content and a tile-based map like you say. I know that's not easy, but maybe something like Godot would be better since it offers much more flexibility and it can still export to most platforms including web. Check out Broken Dreams Correctional Center which is made with it. Assuming good intentions though, best of luck!