black tips/discolour on dracula leaves

[Sylorna]

Hi all
I have written in this forum before regarding a dracula that I didn't get to work in our new apartment. We just went to the orchid show in Burlington and my boyfriend got himself one that was happy, healthy and flowering. We have only had it here for a week and it is already having problems.
First the current bloom died, then he lost a couple leaves, then he forgot to water it (and it dried out completely) and he lost the bud as well. The leaves are progressively getting black/yellowing and more and more of them are getting black tips.
Conditions:
it is hanging in a plastic hanging pot (with holes in the base) in sphagnum moss. We have it at the back of the living room where it gets no direct sunlight, but does get some indirect light during the day. He has been watering it with RO water and it has not completely dried out with the exception of yesterday when he soaked it when he found it. No fertilizer. We also have it directly above my humidifier which is set to 45% humidity. It is nowhere where it could catch a draft. The apartment stays around 70F most of the time (no, there's nowhere colder).

Any thoughts?
Sylorna