So, your intros are going really good and I would definitely be doing the next step which is scrubbing down the cage and moving them in together.
Have you been doing cage switching with them? That's not a big deal if you haven't...but what I'd be doing, scrub it down, do an out time/intro but access to the newly cleaned cage set up at their new home. After the out time, put them in, close it up and watch them for the full day.