You shouldn’t be smoosh and petting in any of their home areas, that should be in a neutral area, as it could cause a fight if you put them in each others territory together while prebonding. You don’t really need to do the smooshing while prebonding.

That isn’t pre bonding. Pre bonding is where you swap them between enclosures, swap toys, blankets, food bowls, water bowls etc. They should not have any contact with one another whilst pre bonding. This is because they need to get used to the presence of one another w/o having the opportunity to show aggression towards each other. The idea is during this process, they may feel angry and want to hurt the other bun/s but they won’t be able too. By the time they do get to be with each other, any aggression should have subsided

When you have done this for at least a month, you can do a physical bonding session but it has to be neutral. You can’t bring bun 1 into bun 2’s area or bun 1 and 2 into bun 3’s area etc.

I just don’t think that’s a safe way of doing it. Can’t you move Storm to a separate room, say the bathroom, then move Harley and Thumper individually to her hutch, then once they’re in hers, move her from the bathroom to theirs.

Having them in each others territory, together, at this stage, is asking for trouble. It’s also more likely to upset H&T’s bond, if one suddenly smells like her.

Alternatively, you could just swap blankets, litter trays and bowls rather than whole hutches.