I had the same problem with a few plants that I grew in a closet to get a head start before putting them outside and the ONLY thing that worked was buying a few hundred lady bugs and keeping the door shut and lights off for a few days. Since it was essentially a closed off area the hungry lady bugs pretty much ate the plants clean. After a few days I put the lights back on and some of them died, some tried to get out and I just let them free, but I say at least 100 or more made the plants there home and reproduced which kept the infestation in check until they where ready to go outside. Just to be on the safe side I bought another few hundred the day I put them outside and put them on the plants as well. All in all I think I spent $15.00 on all 3 bags of lady bugs and the only work I had to do was open the bag.
Good luck with anything else as I tried just about everything and wasted a lot of time and money.