Damaged bottom bracket threads

[larmalade]

Hey, I built, then later disassembled a ebike based on the tongsheng TSDZ2 motor. The motor ended up mashing the threads inside the bottom bracket. Is this an unavoidable aspect of putting a mid mount motor in a threaded bottom bracket? I'd like to avoid this with future e-builds. I know there are bike with non-threaded bottom brackets, but only a few manufacturers built them.

If anyone has advice on how to avoid mashing the BB threads, that would be great!