The Snopes page doesn't refute the claims of weather modification. It just seems to clarify that it wasn't buried, and that it was covered by the media. Such as this article from the LA Times: http://www.latimes.com/local/lanow/la-me-ln-l-a-officials-seeded-clouds-during-el-nino-storm-in-hopes-of-more-rain-20160308-story.html
I agree that widescale/global geoengineering is a drastic measure that should not be attempted. As for localized cloud seeding, I don't know. The health hazards to humans from these two documents don't sound alarmingly bad from low exposure. The MSDS does say "Very toxic to aquatic life with long lasting effects" which stands out.
http://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+2930
The silver iodide would be better used making photographic film and print paper :)