How do I save my dried out Phal

[RosieC]

Hi, I'm new here but I hope someone can give me some advice.

I have a problem with one of my three Phals (unforunately it's my favorite of the three).
I think it has got too dry and I'm wondering what to do to help it recover.

I've just come back from a week away and the weather turned unexpectedly hot while I was away. The other two which I bought this spring look fine. But the older one which I've had about three years is looking really ill.

I re-potted this one at the beginning of June and I had to cut away some dead roots (they were dry and dead not mushy). I was very careful to keep it humid for a month then put it back with the other two, and it was doing well when I went away last week with the new leaf growing well, new extenstions starting to grow on two of the arial roots and even a new flower stem apearing. (I know it's the wrong time of year but all three have got new flower stems having already flowered in the spring).

When I got back it has six of the nine leaves looking wrinkled and wilted. The lowest two are yellowed as well. The top two were limp but not wrinkled and seem to have strengthened already with a bit of water. The new leaf seemed still OK when I got back.

So is there more that I can do?
Is the answer to keep it humid again like when it was repotted?
Will the wrinkled leaves ever recover or am I just trying to save the rest of the plant?
Does it sound like this plant will survive at all (it has loverly deep purple flowers and I would hate to loose it)?

It would be great if anyone has advice.