Oscam to Oscam setup

I've been reading this forum and trying solutions for weeks now, it seems I'm missing some small detail and now I ask for help.

I'm running E2 on a solo 4K with Oscam installed and running, had one local card, all working fine.
Got another card and installed that as well, no problems.
Decided to get another box for the bedroom (duo2) and since I had a spare RaspberryPi laying around figured it would be neat to get that going acting like a server, and this is where it all gets confusing.

I was hoping that I could leave my cards in my 4K, share them with my raspberryPi and then use them from there in my new box, is that correct or am I asking for trouble?

Without going into detail how would the traffic in that setup look like?

As of right now:
Oscam on 4K has two internal readers for local cards and one CCCAM reader from the Raspberry showing (0 of 0 cards), it also has DVBAPI enabled for AU so that box is more or less managing itself.
Oscam on Raspberry has one CCCAM connection to 4K, showing (0 of 2 cards) all well here I guess?
My Duo2 (where I've been unable to start oscam webif so have no idea what oscam is doing) is running CCCAM with a C-line connecting to my Raspberry.

Why is my 4K showing 0 cards, are they not forwarded from my Raspberry correctly or is that a "feature" since those cards are actually local and it knows that?
My Duo2 isn't really doing much, black screen and no requests in the logs on the Raspberry, at least I can see that the user is connected.
I've been meaning to flash my Duo2 with another version and see if I can connect through oscam properly but I've been putting that aside hoping that I could get it to work anyway...

Basically is my whole setup prone to failure or should it technically work and I need to upload some configs for you to look through?

Thank you in advance!

Yeah, I like tinkering.
Re-installed BH on my duo and got another version of OSCAM on it (11160) and now I can access the webif as usual.

Changed the connection to my 4K and got the same as from my raspberry, 0 of 2 cards showing.
Now I tried copying my settings from my 4K to the raspberry and changed the connection back, same result 0 of 0 cards.
Thinking it has to be config related rather than reader/user?

Going through my settings just now it all just sprang to life, seems the problem was cccreshare and cccmaxhops, changing to 0/2 seemed to do the trick.
It's getting late so will have to connect everything back tomorrow, at least the cards are showing up now, here's to hoping!