I don't work with liquid emulsion so I can't say for sure if I experienced the same thing but in my experience if you use a hardening fixer you get these kinds of results. The matrix is so incredibly hard to get the ink to stick right, even if the bleach step appears to have done its job properly (just like how you mentioned). I wind up only being able to get a slight ghost image in times like that and only using a brayer back and forth rapidly. No brush will work, and also no fancy brush work will work. Only the brayer works (in my case). When I do bromoil now, I stay away from using any normal fixer and I mix up sodium thiosulphate from raw crystals. It takes longer to fix prints this way but then you don't harden the emulsion and thus destroy the ability for the bleach to do its thing later on.