The reason the player models are seperate across servers is because of the bones/skeletons. On surf it's not crucial to see when someone is holding a gun, but on jailbreak it is. The player models not on jailbreak, but on other servers, have outdated bones thus would make it hard to see if someone is holding a gun. This would be very unfair towards CTs if they are looking at someone then get shot out of no where.
The only way to fix them is to recompile and fix the skeletons. None of us know how to do this, so we would have to pay someone to do it for us. If people are willing to pay for the models to be fixed, we can update them and share them across servers. If you are willing to do so, shoot me a pm with the model name and I'll contact the modeler to do it for us.