If ACCESSORIES is newer (I know you don't want to say if they are still in colony status or not so you won't get outed
) and they are a good deal smaller, they may be having events after the main informal rush activities are over and/or having a national team come in.
And yeah - unless it was something HUGE (i.e. the triple in-house legacy to BBB suiciding my chapter of AAA) you don't remember who put what down on their bid card from semester to semester.