So it's down to a contest of whether to trust the government of Iran, or a cloud vendor status page?

Maybe we can check something hosted in Oracle Cloud as the tiebreaker?

No, most likely Iran actually launched missiles targeted at the Oracle datacenter, but they were intercepted. The UAE successfully intercepts about 90% of incoming Iranian drones and missiles.

Then Iran then claims the attack was successful for domestic propaganda purposes, and since there is no internet in Iran, nobody can verify if it was actually successful.