Flea infestation in one room - am I going about this right?

I have a room that is pretty much dedicated to my cat. Walked in barefoot to clean her little box (usually I have shoes on to do it when I get home or am leaving the house) and lo and behold, I was attacked by fleas. There is a large area rug and a cat tree in there, but I’ve removed everything else. I’ve been vacuuming daily, leaving plates of dish soapy water under a lamp, and I covered the carpet and the cat tree with diatomaceous earth today, which I scrubbed into the carpet/tree with a brush, and I plan to vacuum it up in 2-3 days. I have put a strip of tape across the bottom of the door for (hopefully) good measure. My dog and cat are on flea treatment meds - they have been for a while - and I haven’t been seeing any on them. I also have given them both a capstar to kill any that might be on them. I have washed all other soft goods in the house - luckily my couch is leather. I haven’t seen them anywhere else (my bedroom, living room, etc.) and my house is hardwood with just a few small rugs. Is there anything else I can/should be doing? How long should I quarantine the room for? I understand diatomaceous earth will not work for eggs - are there any good treatments for that to avoid re-infestation? Thank you!!