Motorola SBG6580 cable modem into Bridge mode on Bright House Networks does not work

I tried placing a Motorola SBG6580 into bridge mode but when I connected via Ethernet to it, I was not able to access the internet or get an IP, I had to statically assign myself a 192.168.100.x IP to access the modem. (I have a diferent modem at home and I can plug my laptop into it and get a public IP address and start browsing the web just fine)

I've read guides like:

but none of these seem to work. When you switch to bridge mode the options limit themselves so you have no access to DHCP or even the passthru option that I could notice.

The router also failed to pull an IPv4 address automatically under it't WAN and Internet settings. (at home I have a pfSense box and it pulled the IPv4 settings automatically just fine)

What else could I try to get this to switch over?

Because it's COAX cable do I need to clone the MAC address over to the router so the ISP can properly find a device to assign IP information too?

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