Seems like if it went in OK, it should be able to turn.
I'd try turning it just a bit with a pipe wrench, in a quiet room.  Listen for rubbing.  Turn it all the way around at least once (some small or cheap motors are not very well centered from the factory).

If it fits in with a few layers of filament tape, it shouldn't rub.
Don't use tape that stretches!

How are the magnets stuck to the rotor now?
There is a chance one jumped to the laminations, and the thing is binding.