Do you have a list of rpm's/lib packages list from your current RHEL server?
I think it should not be that challenging, I am not guru but my line of thinking is produce a list on source server and then compare it with "target" server.
Say rpm packages.
Output produced by this one should be saved, perhaps if you want, you can lock it by chmod and then read then on target server and report anything which is missing?
Please let me know if you want code for redirection and reading.