Go ahead and tell me if I'm wrong but does your setup look something like the below?

So basically you're asking if a INDIlib servers can be joined, running your original one outside together with a new one inside. Looking at:
"indilib.org/what-is-indi/features.html" it mentions "intermediate servers" however in www.clearskyinstitute.com/INDI/INDI-1.5.pdf it becomes clear from the drawing on p.2 that is not what you could use in my glansing impression. Sorry, I'm of no help ;-)

Jasem might have written up some manual for it though as promised at: indilib.org/forum/wish-list/811-connecti...di-servers.html#7055 ;-)

"Chaining" seems to be possible but I don't know if it's desirable for the small problem you try to solve. Nighty night.