Arduino Giga RTC doesn't remember the time

[gilshultz]

@chosenatrandom

I do need to get it working reliably

There are many possible problems, post an annotated schematic showing exactly how this is wired.

@chosenatrandom

3.24v between VRTC and GND.

That would be about right with a fresh battery. Also try another RTC chip as it is possible it got zapped in handling.