Surveillance caught RC outside during the time period after the alarm went off so he couldn't have moved the body during that time, unless an accomplice moved it. However, LE has stated there will be no additional arrests (time will tell).
If it was premeditated (and I think it was), then he had the time to move the body. The constant card swipes I think were the result of hasty cleanup. And how could anyone else even get into this building if not through the the usual entry points all of which having security cameras, right? If someone else was involved, I'm sure they would know by now.