50’ Connection Between Mac and DAC

I’m currently wirelessly streaming CD rez AIFF files from iTunes on a 2017 iMac to my main system (2 rooms away) using an older Airport Express device. I want to go with a wired connection from the Mac to a DAC (Looking at the Schiit Bifrost 2 or, less likely, a Chord Qutest.) which will reside in the rack with the main system......I really don’t want to purchase a dedicated streamer at this point. My understanding is that connection runs of this length are best done with something called SPDIF coax (??). Can this be divided up in such a way that I could use 3 runs of this coax - one from the Mac to an adjacent wall plate, an attic run, and then a third run from a wall plate adjacent to the main system to the DAC? If this is possible, would it be a significant SQ improvement over what I’m using now?

I totally do not understand why you would go this route when you could install Roon server on your Mac and put a Pi based Roon player in your rack for less than $200 and be done with this, while gaining iPhone/Android remote capabilities.
Please excuse my lack of knowledge on this... would this roon/(Raspberry Pi??) Setup negate the need for a DAC? If so, can the Pi device be purchased as plug-and-play for this application? Thanks.
Hi OP:

The pi acts as a receiver/converter.  It will take what your mac sends and output via USB.

Your Mac will need to be on and on the network to serve as the Roon server