It does sound like your rear axle has rotated backward a bit. Not sure how to pull it back, but sure, if a come-along would do it sure, why not. I would not remove the other radius arm yet.
Also--and this is NOT related to your problem--but if I recall correctly, on mine, when I pulled the bolt out and the radius arm off a spacer fell off the bolt and onto the floor. I didn't see it then but when I was trying bolt the radius arm back on I noticed it could move from side to side. I didn't notice what was going on until I looked at the other radius arm.
Just a word to the wise. It is one of those things that you might not notice, but is part no. 14-830, Distance Piece in the Victoria British catalog. The catalog is wrong, however only one per side is required, not two.