Can I cut a pseudobulb in half for rot?

[Rowangreen]

I have a brassia hybrid young plant that's developed a bit of rot at the top of a pulb that seems to be slowly moving down Problem is, it's the best bulb the plant has: it has a new growth started recently, and I don't think the two older bulbs it has have great root systems. Could cutting half the top off the bulb work? I think I have to make a decision fast...

I recently lost two maxillarias and have a third on death row from rot at the base. This seems to be slower, so I'm hoping it's not the same bug/culture problem.

Plant is a seed-grown one and I think I may have got the finiky lemon as it's always had some bit tatty since I got it sigh.