Ezgo RXV Allied Lithium

[Clandon]

I own a 2009 EZGO RXV. Trojan Batteries were just retired. They worked, as well as the charger, but would only last 2 or 3 holes...a mile or so.
I decided to switch to Allied Lithium for several reasons, mostly because the cost was not too much more than new lead battery. Upon installation, I attempted to charge. The little green light came on....very dim, then went out completely. Never charged. I called the battery manufacturer and they recommended a (required) lithium charger.
Still no charge. Replaced the charge port... (with thermistor ?) still no charge...
I really don’t think it has anything to do with the batteries.
If I plug it in, and turn it on, lightly touch the gas pedal, the charger shows 1-3 amp charge, then quickly fades. batteries have 12.1Vs each.. currently. Any recommendations?