underwatering solutions for phals

[Katrina33]

I recently noticed that my very healthy phal
was wilting badly. The leaves seemed lifeless. When I looked at the roots underneath
the growing material, they were soggy and black.
It had wonderful and plenty of air roots so after removing the dead roots I repotted it.Then it began to wilt badly again.
After I submerged some of the air roots in the growing medium, it seems to have improved. Was that the right thing to do? The medium is a mix of coconut husk, charcoal and perlite. I also have two
very healthy cattleyas growing in the same medium with both air roots and submerged roots.
Any advice will be greatly appreciated.