Modem Recommendation

I recently switched to Comcast after almost 15 years with Fios.  We have an extensive MoCA set up, which I would like to continue to use.

I tried using my existing Fios g1100 router by connecting it to the Arris T25 Surfboard with no luck.  It works fine as a wired/wireless router, but doesn't seem to enable the MoCA network, even though I used the right kind of splitter that was recommended in other threads for the coax.   I'm not sure if I have to adjust the settings more, or if the wiring isn't quite right.  There is a splitter where the line comes into the house, with one cable running to the router and another the moca junction box.  That is not how it was with the Fios setup, but I don't know if it makes a difference.

(EDITED FOR CLARITY: The post keeps cutting out the last sentence when I refer to the Comcast tech.)

EDIT TO ADD: I did buy an old xb3 modem off e-bay, but Comcast was unable/unwilling to activate it, claiming that it was a rental device and I would have to pay $15/month for it as a rental.  So I'm skeptical of going that route again.

Rather than go through the hassle of all that, I'm looking to buy (not rent) a modem/router that has MoCA and a voice phone line.    Since most of our streaming is internal (Plex media server, Steam Link), we only have 300 mbps service, so it doesn't need to be especially high end.  Not a lot of modems have the phone jack, so that seems to limit my options.  Any suggestions are welcome!