DVCC ON = MPPT not charging at all with GSL batteries

System: grid connected, ESS - Optimized without battery life, min soc 60%, grid feed-in DC on

Cerbo GX v2.6

Quattro 48/3000/35-2x50 120V fw: 476

SmartSolar MPPT VE.Can 250/100 rev2 v3.02 attached with 1800w of pv

GSL energy 5kw 51.2v 100amp battery connected via bms-can and show up as pylontech battery shows health, voltage, soc etc (params CVL-56v CCL-120a DCL-120a)

problem:

when i have DVCC enabled with pylontech recommended settings MPPT shows external control but wont charge or push power to loads or feed-in to the grid

if i disable DVCC and restart quattro its charging battery and feeding load/grid (shows error 67 no-BMS, i think i can reset mppt to defaults and this will clear)

question:

why mppt is getting throttled/turn off?

do i actually need dvcc on? (even though docs say you should have it on if its a smart bms connected battery)

is it not functioning correctly because its not actually pylontech battery even though BMS seems to be the same?

any other input or experience with this problem?

thank you