Thanks so much for all the pointers! 1, 3, 4 I will give them a try. I’ll have to see how to disconnect the threaded rod from the motor so that I can roll it on a surface (I’ve done similar with arrows in the past).

For 2, the top is open, nothing was modified. This printer was bought used years ago (maybe 4-5 years ago) and used to print perfectly. It was not used for the last 3 or so, and has gone through several moves. When we unboxed it again, there were a few broken parts that we had to reprint (the upper stabilizers that go around the support rod and threaded rod, and the y axis motor mount in the back). So it’s not inconceivable to think one or both of the rods could have been bent as well.