Why would she need to go out to spend the night with someone? She had her own home, no house mates that may be upset by overnight guests and she had another early start next day.
I think if you ask most people who have dated they have done both, had people stay at yours and stayed you stayed at theirs so I wouldnt read too much into that.
There is of course need to consider if the person CL or the man didnt want to spend the night at hers for a specific reason, was he local, was he married and didnt want to be seen at CL's