Renantheras virus/sunken dark spots - help!

[mpiggy]

Purchased this Renantheras about 2 months ago while it was going out of bloom (see picture).

It is kept in a warm room w/direct sun in a south facing room in Maryland. I had repotted it in a vase half way filled with water to encourage humidity around the roots. The plant itself is planted in a pot filled with lava rock that sits in the mouth of a 1/3 filled vase. The vase water does not touch the roots or the pot. However, I can see humidity droplets inside the glass of the vase. I water every other day with very weak fertilization. This technique has worked well a vanda.

I returned home after a 4 day work trip this afternoon and was alarmed when I saw the leaves (see pictures). The room temperature may have dipped down to 50 degrees. I know I need to intervene immediately - but not sure what I should do.

1) I plan to remove the diseased leaves and spray with physan.

2) Should I also repot in coarse orchid mix? And try to grow it more similar to my thriving phalenopsis?

3) What roots should I be focusing on? Those in the pot or those growing a foot above the plant base?

This is my first Renantheras. I have about 10 phalenopsis and 5 catleyas that grow/bloom fine for me. I keep a vanda is a similar vase set-up. This is my first major case of a virus and I'm alarmed!!

Please advise.

Thanks!!