As you see, a diamond is no good. All declarers who got a diamond lead made 9 tricks, doing the normal thing in hearts.
The declarers who received a heart lead all failed. The play is interesting.
You win the heart to play a spade to the J-Q.
North returns an honest
♦9. You finesse to South's
♦Q who exits with - say - a heart.
If the next trick goes
♠9-T-K-A, you are down, making no spade tricks since South's
♠8 is master.
Should you cover
♠10? It's not clear.
If North has
♠A86 left, the suit is doomed. You'll probably need clubs 3-3, or maybe stripping red suits to throw North in with a club. That would work but it's obscure.
Winning is to duck South's
♠10. You can win South's exit, play 2 rounds of clubs if you like to get that bad news, then make on 3-3 spades.
That seem the best shot to me.
However, South should not cover
♠9! Declarer will likely fly king, not wanting to go down in an embarrassing fashion when South started with
♠A83.
Still, if South had
♠A together with
♦KQxxx(x), a diamond would have been led. Quite puzzling.