That is quite interesting! Generally this Bad cast node would come from the class not existing or not being read at the time. After checking over the BP itself, I don’t see anything that could cause these effects.
The Get Game Mode node having an error is odd because there is always a GM, even if it’s the default. Does this still error out if you’re just printing the GM’s name itself from the Get Game Mode node?
Is this pawn in the persistent level or a sub level?
I haven’t been able to reconstruct this issue just casting to GMs that inherit from children or GM base itself. It’s possible the engine installation could have had an issue but very unlikely as this affects binary files, so I’m also leaning on bug.