CAX80 not compatible with Comcast/Xfinity??

Recently purchased a Nighthawk AX8 Cable modem & router, which according to the description provided by Netgear, is compatible with Xfinity. After several months of trying to replace the Arris modem Xfinity provided with this one and spending hours on the phone with Xfinity Support (worst support ever) they are taking the position that this modem is not compaitble with Xfinity becasue it doesn't show up on their "Certified" list. (see below). 

Before I duke it our with them again, I would like to know from the community if (a) this one is in fact compaitble as advertised and (b) is there some specific steps to getting to to work with Xfinity??  I am setting this up for a non-profit and they are on Comcast Business with a Fixed IP address. I pluged in all the appropriate settings for Fixed IP, Mask, DNS, etc. and it took it in just fine. However the "product support person" from Comcast said she couldnt' get it to initialize with her system which evidently has a preconfigured script it uses to ping the modem by MAC address and then push the appropriate signal to establish a WAN link. I watched as she attempted to do this and none of the settings she supposedly used made the WAN connection. 

So, looking for some others who've set one of these up on Xfinity and perhaps ssme tips on getting it to synch up with them. 

Thank you. 

:smileyhappy:

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