Thanks to @Emil Jeřábek for findingfinding the author of the question, whowhom I have now e-mailed. (ETA: it'sit's back now!)
Thanks also to @Martin Sleziak for his answer in commentscomments to the meta-question of "how do I find the author of/other info on a deleted question?"
I will just add that the deleted question (and, consequently, the OP) can be seen by 10k+ users. And anybody can see the question in Google Cache - at least for some short period of time. – Martin Sleziak