Any hope for a Miltonia with no roots?

[snail]

I bought a whole box full of orchids for next to nothing at a garden center yesterday. They are a sad looking bunch that had finished flowering and they wanted rid of, I couldn't resist rescuing them. They are not suffering from disease as such, mostly just over or under watering.

Most of them are phals which do well for me but I also got three Miltonia which I've never grown before. I got them out of their pots and started to cut off dead roots, I thought I could save some root but it turns out they were all rotted. What now?

The leaves still look reasonably healthy (only very slight general yellowing) and the core is not effected by the rot but I'm left with a plant without roots. Any suggestions what to do? Do I have a hope of getting new roots to grow? I planned to try semi-hydro (which I'm new to) on the plants but will go with whatever is best for a chance of recovery. I've got an empty aquarium I can turn into a hospital if it helps.