Well that is odd.
I just looked at the preview and the actual treasury, and it appears that the two items in the preview that are not showing up are similar clothing items. I don't know if this has anything to do with it, but it was an observation.
If the clothing items were purchased, would that possibly cause them to disappear from the treasury? I've made treasuries where items have sold, and I believe they stayed there, and just said "sold" when you clicked on them.