I know that sounds like a stupid ass question. I have the Logitech wireless mx keys. I wiped the keyboard down so the surface of the keys aren’t sticky, just hard to press down and some have a spasm.
Since a whole ass thing of coffee did not short it, it gives some credibility that it is water resistant. Can I just dump water on it to help it?
Did a quick search and it looks like it uses Kalih Choc V2 mechanical switches. The each key cap should be held on to the switch by a friction fit. You should be able to pull each key cap off then soak them in some soapy water. If you don’t have a key cap puller, you can try using some string and a pencil or wooden dowel to make a cheap one.
Although from what you described, coffee may have gotten into some of the switches. That would require replacing the sticky switches or taking them apart, cleaning, and re-lubing them. In either case, pulling the key caps will give you a better idea of where all the fluid ended up.
Some people have recommended alcohol. If that gets into the switch it will dissolve the lubricant.
I would say pull a couple keys you care the least about then take a closer look before you decide how you want to tackle cleaning it.
https://www.kailh.net/products/kailh-choc-v2-low-profile-switch-set
It’s this one
https://a.co/d/3ejciJE
That’s a scissor switch which you have to tackle a different way. So disregard most of what I’ve said. Coffee residue is likely gunking up the plastic switches. You can try to find a guide to take those apart, but they can be a little more delicate.
ifixit has a couple guides for how to take the keyboard apart. That will let you separate the electronics from the switch assembly.
I got something (coffee, or possibly a bit of soda) in my mx (exact same model) and I just spritzed it out with 98% isopropyl and let it air dry. Now about 70% of the backlight doesn’t work. Kind of a fail, really.