I'm certainly not saying that you are being silly for worrying about this, at all. But dont worry about it. I didnt think of this at all with my twins because they are b/g. But the triplets I did, especially when we didnt know if the boys were ID (still don't) and because I had assigned names to them based on their birth order and in utero personalities. And because at the 20 week scan they were flagged for all kinds of 'problems' that were either going to be nothing at all, or a big deal, and I was worried that they would lose track of people, especially with the 12,000 staff in the deliveries. FTR: they were all nothing.
There will be teams that are specifically assigned to each baby and they will be with that baby every second. They will be banded right away with A, B, C etc. Funnily enough, my baby B was readmitted to the NICU a while after being discharged for something totally unrelated to birth and was STILL Baby B Lastname even when Babies A and C weren't in the hospital anymore.
With my triplets, they scanned me before I went into the c/s, and then while I was on the table for last minute presentation. It was obvious for us since baby A was jammed so far down into my cervix that there was absolutely no physical way anyone else could have got even a pinkie toe ahead of him, but they were still aware of it and made sure everyone was accounted for correctly. :)
Adalines mama, I dont know if you were talking to me asking for a picture, but here is one anyway. :p