Planaria are NOT dangerous to shrimp, fish, eggs or larvae. That's been my experience running multiple hundreds of tanks large and small over many years of fish keeping
There is quite a lot of mis information online which started around the time anti planaria treatments became available. Some of it very persuasive, some of it very intimidating, some of it very scientific, some of it very logical, some of it plain stupid as well but no one I personally know has found planaria dangerous either. Poor cute little worms. They are only trying to correct a surplus of uneaten food and make great source of live food for fish.
So much crap online these days.