Fallen Leaf, Mini Phal - Don't think it's crown rot

[MrsH530]

Hi everyone!

I had a weird problem on one of my mini phals. I was doing my weekly watering this morning, and noticed that the top leaf on my mini phal was wrinkly. I thought perhaps it got a little dry, since we have been having weird weather, but when I touched it, it fell off.

My first thought was crown rot, but after inspecting closely, I can't see any evidence of it. No other leaves show signs of damage and the crown appears fine to me.

Roots are healthy. No decayed or dehydrated roots.

The leaf that fell off feels really soft and mushy (yuck!!), and the underside is bubbly. I've attached pictures. Any guesses what it is??

The spike was finished, so I cut it off this morning. It has been in bloom since I purchased it in February. My watering schedule is 1x week rotating between fertilizer, Ray's rooting seaweed, and a regular water flush. One other time a week I go through with a spray bottle and mist anyone who is looking a little dry, to hold them off till the next watering.

Any help is appreciated!