I like the rock, but I can't verify safety from the photo.
As long as your BP can't get wedged in and stuck, can't crawl up behind anything and get stuck, as long as there are no pokey wires or sharp edges sticking out ...it should be fine. ( I would snip off that one vertical pokey bit of stick if it were my enclosure.)
Snakes have all day to think of ways to get into trouble - in ways you would never imagine.