Hi HU-585149926! I don't have any technical advice about the job but I wanted to let you know that you aren't alone in hiring/trusting trade people based on a friend's recommendation. My husband and I had a similar situation last year. Our first major reno also. Our friend owned the company and his employee/contractor (who was also the tile guy) ended up walking off the job before completing the tiling in the main bath (we renovated the main and guest bathrooms). Like you, we have learned a ton of what not to do if ever we take on a reno project again. Thankfully, we hadn't paid him everything. In the end, we had to find other contractors to finish up everything (during the first weeks of the COVID situation) and ended up not paying anything else to the friend/contractor. Unfortunately, the situation did "taint" the friendship. I just wanted to offer encouragement. It's likely going to take more work and frustration on your part, but keep plugging along. Good luck!

The tile job is fine. The tiles in the corner are not running the wrong direction - they are just the pieces that can fit so your tile could run to the edge of the countertop. It's much better to have full tiles at the end of the countertop where you see them more than back in the corner. For the butcherblock, that can be filled in with wood putty or filler, but you should let the tiler know not to be cutting anything on the countertop.

get some clear plastic shelf liner stuff that has holes in it / looks like expanded lattice and cut it to fit. It will be generally unnoticeable and will grip your bottles AND water will drain out. I guess alternatively, you could find some clear silicone or rubber dots / stips like you put on cabinet doors and stick to the tiles. These solutions are cheap, replaceable and fairly invisible. And if the rest of the shower was done well - 1000% non-invasive.

Not a great job here! You need to document with photos and contact contractor/installer. I hate to be negative but keep track in writing of of complaint (follow-up direct conversations with email for record). Hopefully, they will take responsibility and repair or replace what is necessary. God luck,