PW4 not charging after battery replacement

[The PCGuy]

Hi all.
I replaced the battery in my PW4 (10th gen) and now have two problems:
1. the battery does not charge and the orange light never illuminates.
2. The Kindle will start up but goes to sleep after a few seconds, regardless of any screen touch inputs.

I have tried reconnecting the original battery, with the same results.

One possible issue - the area highlighted in the attached pic shows 4 pairs of pads adjacent to the batttery connector. Only 2 of these have components fitted and I was wondering if my hamfisted removal of the battery connector had knocked a component off the board!
I have so far failed to come up with any schematic or layout information for the PCB, so i'm pretty much in the dark as to what to try next.
Has anyone ever come across this or have any suggestions as to where to look?

Many thanks