guys I have been freezing fresh shrooms in the past and they didn't turn to mush when they thawed. They do leaked water but the mushroom structure was fairly preserved. That was with B+ strain (in case the mush result is strain-specific).

I largely believe that the frozen-shrooms-turning-to-mush is mostly a myth (based however on a good educated guess of what might happen...) and that few if any have ever tried that themselves.

Just for the record I was freezing shrooms as at that time I preferred to eat them as is, frozen straight out of the freezer, like icecream sticks - when my freezer died I had the chance to observe, in my surprise that they did not turn to mush.