Update:
The kids didn't show up. The apartment manager came by and hubby went out to talk to her. Mentioned that we had been talking to the couple who left so abruptly. The manager said that they had just called asking for their old apartment back and promising to pay all the arrears. The manager ain't going for it because of how they left with out notice or paying rent and the sorry state they left the apartment in. Didn't clean it, partially painted walls (picture painting around a bed and not behind it) and somehow broke and took out a doorframe from one of the bedrooms. We warned them not to burn any bridges.