Hello Elias
It’s not completely clear to me the topology that you’re describing, but it sounds like you’re on the right track. In order to resolve the issue, you may want to take a look at policy NAT using route maps as a solution. I can’t help you specifically without knowing more details of your topology and addressing scheme, but I suggest that you take a look at this lesson for more information:
With policy NAT you can allow the specific traffic defined in your access list to be NAT’d, while not affecting the other services using the same Private IP.
Let us know how you get along, and if we can be of further help.
I hope this has been helpful!
Laz