Switch Lite charging 15v and 5v 0.48a on low battery 0.25a on charged battery - Not powering on

I have a NIntendo Switch that had a visually damaged charging port. Replaced the port, Switch now charges but doesn’t power on.

I’ve got 15v and 5v on board with mains connected but battery disconnected, 3.3v at battery connector. No shorts on M92T36 or BQ24193.

I’ve tried the board in another housing with working power button, display etc, still no signs of life.

I don’t know what else to look. The board isn’t heating up in any noticeable way.

Any advice?