Angraecum birrimense pot size question/emergency repot

[BrassavolaStars]

Hello all,

I have this Angraecum birrimense I got only 10 days ago. When I first got it, it seemed alright but the leaves started to wrinkle this past couple of days so I took a close look in the pot and the bark was extremely broken down (the consistency of wet paper) and it was covered in mold and a beige paste that I could only begin to guess at what it was. Unfortunately, many of the roots fell off taking it out of the pot. I have just doused it in clearys and physan.

How do you all recommend I pot what is left? What medium should I use? Most importantly, how big of a pot? I don’t really want to mount it so that’s the only thing off the table but I’m open to baskets. I would like to do the thing for this plant culturally to get it on the mend.

I am not sure how this happened. I watered it maybe once or twice in that 10 day interval and I also had sunny and high temperatures for most of the week in my GH.

Edit: I should add some perspective to the photo. The plant with the roots made into a pot shape is about 17 inches.