Hardware Official dock display suddenly not working

[angerized]

Hello,

I bought an amazon refurbished splatoon 2 pack for my brother (let's call him brother 2). It came with 7.0.1 out of the box (not that it is really relevant). It was in pretty good shape apart from a slight scratch on the side, after all it was refurbished.

I did not try its dock, but I installed atmosphere and all was good.

My other brother (brother 1) put that switch on his own dock to charge it prior to offering it to brother 2.

Brother 2 tried it back at home and the refurbished switch's dock did not display picture (charging is fine though).

Now on the the mystery: Brother 1's dock is not displaying anything anymore (only charging).

Here's what I tried:
- My own switch on brother 1's dock: not working
- Brother 1's switch on my own dock (with his hdmi and usb cables): working (so no problem with the cables)
- Disassembled brother 1's dock, trying to plug it as is (USB C both ways): not working

Brother 2 is in Japan ATM, so I can't try his switch or his dock right now.

I do not really want to brick my dock while testing brother 2's switch on mine, but I think I will do some more "safe" tests when he comes back from Japan.

Could it be that his switch is bricking docks? has anyone experienced something weird like that?

Thanks.

 

[angerized]

So I'm replying to myself, for what it's worth.

After extensive testing:
- Brother 1's dock is fubar.
- Brother 2's dock is fubar.

I put a COOV hboard i3 inside brother 1's dock to fix it.

- Brother 1's switch TV out is working now.
- Brother 2's switch does not work with the COOV hboard i3 TV out. BUT it did not fry it, like it did originally (thank god).

Turns out Brother 2's switch was somehow fucked up, and Amazon accepted a return, even if it was a refurbished and the 30-day return window was closed. Thanks to them.

I bought another switch for Brother 2 (new, old stock), and this is the end of this miserable story.