Here we go again. I know he's a good person with good intentions, but he could've worded it well. So I find myself on neither side of this dispute. My evidence? That his Dua needs to be explained.
I will, however, say that I don't think it was good to say that the pandemic is caused by immorality, because it undermines the scientific way of thinking.
To raise moral concerns is good and a right, but he shouldn't have linked it with the pandemic so firmly. Again, read above.
Why this pandemic happened from a spiritual lens, we don't know, that is the knowledge of the unseen, God knows best.