Those are root primordia ie your plant was beginning to grow roots. Just as you had wanted. Sadly you threw out a bunch of successful cuttings right in the middle of the propagation process.

You may be unpersuaded but I promise you that your picture shows the phenomenon I have described. It happens particularly in very high humidity and warmth. It's not a disease. Fungus would have been easiy brushed off with a swipe of the finger.

Obviously you can reject my answer if you wish but I stand by it. I've been growing and reading about growing for many decades too and I have seen this phenomenon. What you see in your images is the callus formation which is part of the indirect organogenesis process. As to the mush there's nothing to say there can't be some rot as well as the incipient roots. Perhaps if it ever happens again you could keep the cuttings and see what happens.

I was wondering if it might be oedema (edema).

Looked like cuttings callusing to form roots to me. Like you see HERE.

tj

I agree, Tsugajunkie, but the OP, who appears to have deleted their comments, disagreed. My posts above were responses to the OP but the deletions now make it look as if I was talking to myself.

I hate it when people do that! I wonder what they do in person when someone is having a discussion with them?

I figured that, floral. You are not one to go on without , shall we say, prompting.

BTW- Not only are the comments gone, but if you click on the OP's name you get "Page not found". Even the OP is gone.

tj