my fenix 5 plus screen has gone blank and keeps flickering

The exact same thing happened to my Fenix 5 Plus Sapphire today after a pool swim. I went swimming this morning and I washed the watch as usual and it was fine even after walking back home but then suddenly next time I looked at the watch after a while, the screen was all black. The backlight still worked and I even got vibrations from received messages etc. but screen was all black.

I tried putting it to charger (should have had more than 50% of charge but anyway), soft reboot or hard-reset but that did not help. Only thing it did was that after the press sequences my phone asked for pin to re-pair with the watch which of course I no longer couldn't do since the watch screen does not display the pin to me. So my watch that I bought only week shy 4 years ago for 750 euros is no completely useless.

To confirm that this is a screen issue, later today my watch screen started flickering and then had some white areas / lines across the screen and looks quite similar to  my watch face (but nothing is readable and pressing buttons doesn't make the image change). Seems that this forum no longer supports images so here is a video of how it flickered and how it was after that (does not filicker any more): https://photos.app.goo.gl/43QeD7vsR5wnvbFF9

I contacted Garmin's Product support earlier today but they only have email support during weekend and it says they answer to emails after 2 working days.... but my guess is that since this watch is already 4 years old, it is not under any kind of warranty and my watch is basically a brick :/ 

Anyway, I need a Garmin, so I ordered a Fenix 6 pro today, which I wouldn't have needed. My 5+ was completely fine for my needs.
And I do know that F6 will run out of software support very soon but I don't want to spend another 750 euros on a Fenix 7 if it will not last 4 years of regular use.