Hey Mike,
Good you are on the road. Just to be clear:
The "Locking bolt" is the piece in the lug under the barrel and completely not your culprit if it was spinning. Make sure you ordered the right piece that you want - Numrich's (egunparts.com) has schematics and parts to help ID these.
The "hand" is usually a part that needs fitment on installation - dropping a different one in may or may not let the gun function. Unless there is pretty obviously damage on the ejector star and hand face, it's also not likely got anything to do with the problem.
You should see a spring in front of the cylinder bolt that rests against the curve of the housing in front of the trigger. If it's missing or bound up, that's your problem. I'll see if I can find a photo and come back and add it. Member
Sylvan_Forge has a sticky at the top of the forum with a model 10 tear down/rebuild. Look there for photos; I think I have some photos of a Victory model disassembly I did a while back, let me see if i can find another photo.
Edit: OK, focus on this:
Look where the crude arrow is. That's the cylinder bolt, the top rounded part that should protrude into the frame window and lock the cylinder in place. Where I circled, there is a spring that makes this happen (as well as the trigger). It may not be apparent in my photo but it is there and needs to be straight and square against the housing wall and then the cylinder bolt, else it will bind and fail to force teh cylinder bolt to return and lock the cylinder.
The cylinder bolt is not usually a "wear" item so it's most likely a spring bind or, as
David E said right up front, an old, dried over-lubrication issue. That was actually the problem with this gun and why I tore it down - someone had packed it solid with valvoline axle grease at some point decades ago and the gun was non-functional until I stripped it out and re-lubed it.
There will be a minor difference in the cylinder bolt spring between the 1942 model pictured and your actual gun, but the concept and location are the same.