Apropos the clothing, it's already been noted that Kelly took in laundry and the occasional female lodger, so it's quite possible that some of the clothing did not belong to Kelly.
We also know Sam that Maria claimed that some of the garments found were her laundry, presumably laundry that she did for others to make a few coins. In that context, I think Mary's proximity to fresh water, the ability to heat that water, and to wash several garments at once in a tub, might have lured Maria there in the first place that day. It was said that they spent the afternoon in that room. We also know that she gave Mary a few coins that night.
In some ways I am more interested in the burnt clothing than the others. I find it puzzling that after sieving ashes Friday afternoon and recovering items from the ashes, Abberline and a few of his squad returned to the room to sieve again Saturday morning. I, like Abberline, think that there may have been some interesting clues in the soot.