Slip yoke issues after drive shaft rebalance

[MYOUNG]

I just got my Two piece drive shaft back from the drive line shop and now my slip yoke will not go into the tail shaft of my transmission.

I have an NV3500 5 speed and it takes a 32 spline slip yoke that I test fitted before giving it to the drive line shop. When I tried it, I was able to slide it on very easy but after getting it back now it will only go on about 1 1/4 inches before it becomes difficult. I tried tapping it with a hammer and it slowly goes in but I was afraid that It would become stuck so I tapped it back out.

I have inspected the inside of the slip yoke and I cant see any "damage" or galling. I was thinking that the shop somehow must have done something to it but I just cant see what the problem is. I thought that they may have given me someone elses slip yoke by mistake but it looks the same. I counted 31 splines plus a small gap where the last spline would be (32). The splines inside of the transmission look good also.

Would it be crazy to go at the inside of the slip yoke with a tiny flap wheel or micro file ??

How do these shops balance the shafts?? Im going to call them tomorrow to see if they can do anything but im guessing they are going so say that they never even touched the splines.