I need help about the Zero2Go Omini Rev2

Hello,

I've bought the Zero2Go Omini Rev2 months ago for a DIY project published on Github with instructions. The author uses the Z2GO to power a RPi 4B with a rechargeable Li-Ion battery (4S, but users now use pre-built ones from vacuum cleaner companies). Everything's fine, once connected to the battery, and after pushing the button on the side of the Z2GO, it turns from blinking red to green and the Pi (and everything else, a display, a fan, LED buttons) turns on.

The tricky part is that he decided to use the XH2.54-2P port as an input for the rechargeable Li-Ion battery and he soldered a DC port on channel B on the opposite side of the board to recharge the battery.

The first time I tried to recharge the battery as instructed, my battery charged, but my Z2GO fried, no blinking red LED and it became hot if I plugged the battery or any other power supply, the board was dead.

I later had a discussion with the author and the only plausible explanation is that my charger was a Lithium charger, not a Li-Ion charger because my battery is a Li-ion type battery.

But right now, even after purchasing another Z2GO with now a new charger that explicitly labels "Li-Ion charger", I'm SO scared to fry the board again.

The author said he had this build for 1.5 years now and he recharged the battery a lot of times without any issues.

Before doing another mistake, what are the other possibilities that could lead the board to fry ? I've talked about the following FAQ :

"No. Zero2Go Omini actually doesn’t know what kind of power supply you connect to
it, and it only sees the voltage on every input channel. If you connect a rechargeable
battery to Zero2Go Omini, it will not be charged by Zero2Go Omini, and you will
need to implement your own charging circuit."

But he said since channel B solder pad and the XH2.54-2P are the "same", I quote "You are just wiring your charger port in parallel with the battery".

Thank you for your advice before another disaster happens haha..