Easiest way to replace battery

After a lot of research on replacing the QC20 battery, I have a few questions. I'm not satisfied with the lack of photos and the explanations online.

The consensus seems to be you need to replace the little board on the battery and you need to match the voltage between new and old battery. Question: Since all of them seem to first strike out with a straight battery swap, they next think they need to exchange that board. Then that fails, and they match the voltage. So if you match the voltage, will the board belonging to the replacement battery work, or do you need to do both?

Some instead use a lipo charger. I've seen Adafruit 1304, 1904 and 4410 and Sparkfun mentioned used in various ways.

The guy who used 1304 (J. Reid on Amazon review) described making a special charging cable. With the 1304 plugging into a charger or power bank, then attaching a micro USB cable on the other end, lopping off the regular USB plug and attaching the leads (soldering?). His description (if I understood it correctly) makes it sound like he's plugging the micro USB end into the micro USB port on the DAC. Since the QC20 won't charge unless you've matched voltage and possibly exchanged the board on the new battery, I suppose that's possible? There's not charging happening on the inside of the DAC. Just want to make sure I won't make anything go poof…

Can someone help me reason if that's what he actually did?

Because that would be the easiest fix. Just attach (easy soldering!) the cables from the old battery and the new without disturbing anything on the board, any board.