I moved it to General FW.
If they were freeze dried bloodworms, I'm assuming they were dead. Sometimes when you feed frozen bloodworms some of them will be living (witnessed this myself, as I found them in the tank later on.......). I doubt they will turn into mosquitos. I have found bloodworms living in the substrate and while I'm not sure how long they had been there, there was no sign of them turning into mosquitos.
This is not my area of expertise though....