I am not an expert, so please take these answers with a grain of salt.
'Shock loss' does not apply to you. It sounds like you've already lost most of the hair you're going to lose off the top of your head. Shock loss is accelerated hair loss for men who are still balding for hair that is already genetically predisposed to fall out. (My interpretation from "Hair Loss & Replacement for Dummies", Rassman). Furthermore, shock loss does not apply to transplanted hair. Don't worry your hair will grow!
Yes it is expected for the transplanted hair to fall out after 10 days.
The minoxidil will not affect the hairs in any way.
You should not have any noticeable death rate for densely packed FUT. If you only did 4000 grafts to cover a full head, that is not super dense, it seems to me. Sounds like you're trawling the internet for bad news.
Your scar will likely be very fine and not noticeable, despite the fact that it is pretty gruesome now. You will not need to correct it. You will not need FUE. You will likely be satisfied with the outcome and not want another procedure.
(One mistake I made, however, on the first HT: don't use too much bacitracin. After a few days, wounds should be kept clean and dry for the most part, though you can apply it sparingly. But you're a health professional so you know that.)
I understand your mortification of the big red line in your head. From my first HT I had staples which made it look like a huge zipper. Frankenstein. Fortunately, I work from home so I didn't have to hide it and no one saw it. But yes, everyone should have a hand mirror after the surgery.
For now, you can ask your doctor if you can use a make-up concealer to hide the redness. This would be like a skin-colored lip stick.
Your irrational fear is that six months from now you will have a bald head and nothing but a huge scar to show for it. LOL. You better show pics in 6 months! Don't worry about the haters. They're just jealous.
Finally, I'm not sure why you don't want to discuss this with your doctor. But you can. Like you said, you paid a lot of money. If you don't trust him, that's another story.