White mold/fungus immediately after repotting!

[aramina12]

So I repotted an (phalaenopsis) orchid for my mom and then less than two days later a leaf is turning yellow from the base to the tip. I come to discover it's likely due to the strange white fuzzies growing over the orchid spike that had been cut back. At first I thought it was maybe from improper scissor sanitation and was freaking out because I repotted four on the same day (three phals and one psychopsis). However, only one of the others appears to be displaying similar issues and it's not immediately by something I cut. I've repotted several orchids before always with the same potting medium (a mixture of sphagnum moss and bark). I even repotted two a couple months ago with medium from the same exact bags and they're doing okay.

Any advice on how to quickly get rid of this issue? Should I isolate them from the rest of my orchids? Any ideas as to what could have caused it?

I've attached a picture below. Apologies if it's difficult to see. I can try taking more pictures tomorrow when there's better lighting.

[Optimist]

Sclerotinia thrive in damp cool conditions.

Less damp and cool may take care of this.

I don't know about the yellow leaf. Did the mold cause it, or was it natural scenescence that just happened to coincide with the white mold.

Check to see if the plant is otherwise healthy. Wash it of mold. Let it dry. Some say leave it unpotted on newspaper about a day, then repot in fresh media in a place not as damp and warm.