Inconsistent battery charge replacement with iFixit Kit?

I recently replaced the battery in my Retina MacBook 2016 with the corresponding iFixit battery and kit.

I followed the instructions to a tee. After finishing the replacement, the charging would flick on and off.

It recharged to full a couple of times, but eventually stopped charging more than 75%...even though the iFixit battery was detected as new via coconutbattery.

I did an SMC reset and it didn't help.

Clues to note:

-The USB-C port would only be detected if I insert it "right side up". Of course, before this, I could insert it either way.

-I could never tell how full the battery really was, even with coconutbattery. It would be 50% full for an uncommonly long time and then suddenly turn off.

-the laptop no longer detects external displays.

Now the laptop is dead and I can't get it to turn on long enough to see if it's actually charging.

Is this a logic board detection issue or a faulty battery?

Any help would be greatly appreciated!

***Update/Edit:

The laptop now only powers up when plugged in, but the battery won't charge, and powers off when the plug is removed.

FYI - that was the state the original battery was in which prompted the replacement. Makes me think there's some bug with the computer or software. It was old, but still worked fine until I updated to Monterey or the previous version.

I finally got it on long enough to snap these shots from coconut battery.