idk maybe sounds like a good idea and i hope it works out for you. only problem i can see is 1) if there are no bugs in your room then the ladybugs will die anyway. or 2) those ladybugs were on the leaf because there was food for them, bugs, eggs whatever. i just hope they eat and kill everything they were feeding on so your room doesnt end up getting infected. a good rule to remember is to never bring anything from outdoors into your indoor operation. including yourself after working in the veg. garden or walking in the woods. your pants or shirt can get pests on them and you wont ever know it until you have a problem. example spidermites, hard to see them until your infested with them.
