3 crystal key room

3 scroll and 3 potion rooms, but only 3 keys. I know the first room is second tier stuff, the middle room is lowest tier and last room is the highest tier. The wiki ranks potions by drop rate and not in 3 tiers.

My question is which potion or scrolls can appear in each of the 3 spots? Can the tiers cross over. Like a scroll is close to both tiers so it could possibly spawn in two of the 3?

I've been taking a lot more notes. I took them before but now I'm doing like everything as to not waste anything. I was going to keep track of this room to make a list, but if someone has a list that would be great