All drives will ultimately fail, could be 10years, could be 10mins. If you don’t want to lose your data, back it up. Have a storage drive and a backup drive. Don’t both connected them to the router. Use an alternative method to connect , like to a computer and have run a backup protocol on a regular basis. As for 2.5 over 3.5, the 3.5 are usually faster but it probably doesn’t matter reliability wise.
I would second the bad disk. I thought bad permission but since since it seems intermittent, the bad disk is the better guess. It would be good to get more info like what’s it running on, is it an array, etc.
Y’a, it’s a total pain in the butt. Angled pliers do work best. Good luck with your fillings. Also having the iMac laying down on the workbench helps.
if the water damaged mac doesn’t turn on, the target made with a thunderbolt cable won’t work. You will have to take out the SSD. For your Mac, you will need a specific drive enclosure to match the SSD. You will also need 2 screwdrivers, a torx5 and a pentalobe for opening the bottom case. Check out owc/max sales. They have the enclosure and the screwdriver kit.
https://eshop.macsales.com/item/OWC/MAU3ENVOYPRO/
https://eshop.macsales.com/item/OWC/TOOLKITMBA/
If the drive is encrypted, when it mounts on the functioning mac, you will get a prompt for the user name and password for the main account of your partner’s laptop.
You may be able order the cable off eBay. Some of the cables have a connector on each end which means you can replace it. If you damaged the connector on the logic board side you are a bit more screwed as that will mean a board replacement. Don’t spend money on new screws, just use needle nose pliers to hold the screw while you screw it in.
If the license is registered to that system changing the hard drive and reinstalling the SAME version of windows won’t be an issue. MS saves your system’s “fingerprint” and as long as you don’t change too many parts, it will recognize it and attach the license back to it.
If you do lose the license on reinstall, there are site that will sell you a cheap license, buyer beware, or ultimately you could switch over to something like truenas (core or scale) to run plex which is license free.