That URL is supposed to be a totally random string generated by YouTube. It's a big ole coinkydink that it says YesQ.
Most likely, the filenames generated by utoob and other hosting websites are generated by a ‘hash’ algorithm, in order to make them unique, or as close to unique as possible.
Otherwise, their directories would be filled with filenames like “catvid1” “catvid2” “funnycat42”, etc.
Can’t have that now, can we?