Stockfish on Big Positions

This position, which is a mate in three (1.Qxb7+ Qxb7 2.Qxb7+ Qxb7 3.Qxb7#) takes Stockfish forever to analyze. Why is this so?

Which position?

Oh. This position: kqQqQqQq/qqqQqQqQ/QqQqQqQq/qQqQqQqQ/QqQqQqQq/qQqQqQqQ/QqQqQqQQ/qQqQqQQK w - - 0 1

Also, this kqQqQqQQ/qqQqQqQQ/qqQqQqQQ/qqQqQqQQ/qqQqQqQQ/qqQqQqQQ/qqQqQqQQ/qqQqQqQK w - - 0 1
is a mate in 6 (1.Qxb8+ Qxb8 2.Qxb8+ Qxb8 3.Qxb8+ Qxb8 4.Qxb8+ Qxb8 5.Qxb8+ Qxb8 6.Qxb8#).

And more here: lichess.org/study/ZpZJTht7

These are not chess positions. Not at all.

illegal positions

While positions are illegal, I'd be impressed if anyone could figure this one out!

Lol

Exactly. They're illegal positions, so why can't Stockfish solve them?