OK, pretty easy to figure out which shops you're talking about :-)
First off I never worry about a 9. To me, a 9 is a 10, and you'll rack up enough 10s that the 9 won't make a difference :-)
I note you did 5 shops. Just an FYI, 4 per day is the limit. Says it in the guidelines but you won't NOT be scheduled, at least that's my experience. I made that booboo once and noticed all but the 5th shop had been scored. I didn't know if that was why so I just emailed and threw myself at the mercy of the court. No email response but suddenly the 5th report was scored.
Next up is the changing number of employees available. Read the guidelines carefully, they tell you exactly how to deal with changing situations like that.
If there was a couple in front of me one of them is closer. I would choose that one then note somewhere in the narrative that it was a couple but when I got in line that one was directly in front of me.
These reports are some of the easiest I've encountered, but that comes with having done a few. Rack up some experience in them and you get an idea of what you need to look for. I strongly suggest getting a digital voice recorder and a mic. I put the mic on the back of my shirt near the collar and it picks up my voice very easily, so I can make notes of what I'm looking at and also record what the employee is saying so I don't have to remember. For restaurants I'll say things like "Tables and chairs clean, floors clean, ceiling tiles clean" etc. I use this for times as well - whenever I start a new recording I state where I'm going and look at my cell phone and call out the exact time down to the second. When I"m on any timed shop I say under my breath "Walking in now", "In line", "Walking out now", and certain other time cues (when I'm called to a register, order total, order served) usually announce themselves and again if they don't I'll make a little under my breath note.
So again the reports are straightforward but like anything else daunting when it's new to you. My advice is that if anything happens that falls outside the bounds of the report's pat answers you should provide voluminous notes documenting it up front.
Sounds like you have a pretty good handle overall and can write intelligently and think logically. You're already ahead of the game in that respect :-) Good luck!