Routing distinct Outbound numbers via distinct trunks (SIP)

Hi all

I’m not sure, if title is correkt, since I wonder if different trunks are needed to resolv my problem.
I have a bunch of independent numbers from the same provider. I can call each one and everything on inbound is fine. Each call is “answered” by defined extension / inbound route.

But calling back showing the correct CID is the problem. There is always the “core” number on display and what ever I do (Outbound CID, …) it doesn’t change.
Only thing I can change is “Trunk Sequence for Matched Routes”, but than each extension calls with the new top most trunk number.

In my point of view, I can’t create a real binding between extension and outbound route.
But maybe this isn’t necessary at all.

But then, what prevents usage of Outbound CID given in each extension?

Thanks in advance!