There is no technology on earth that can make storms of this scale. Cloud seeding doesn’t add any water to the cloud. At most, it causes a very slight increase in rain. If you accidentally cloud seed “too much” you nucleate lots of ice crystals within the cloud, making many tiny ice crystals (which don’t precipitate at all).
They didn’t seed this cloud - but it wouldn’t have done anything if they had.
If you mean climate change, then yeah, obviously humans do influence the climate. In terms of individual scale events (weather, big storms) there’s not any existing technology that exists that can cause a single targeted big storm event.