Yeah, that's why I said "most of the time". Point remains the same, she never change her territory. So they can challenge her almost anytime but since she is not hurt that much for decades means that the admirals may have never challenge her or that they never able to bypass her durability.
BM statement may mean two things. 1. Admirals never went to her territory to fight her.
2. Admirals never able to bypass her durability.
Its not like BM went running away, she stays on WCI most of the time, admirals may attack her anytime they want.
It is interesting to note too that Number 3 has a rope-like necklace and Number 1 has a rope-like belt. This kind of accessories are most common on wano. I wouldn't be surprise if 1 and 3 are really those guys and 2 is someone else.