I am really curious to hear about the testing done on the bale of hay. When we had horses, occasionally we would come across a bale that was black due to mold....or if we left a rubber feed bin/water bucket on a bale of hay for too long. If the tote was placed on the top of the hay bales as reported, on one specific bale of hay, and retrieved 48/72 hours later, it seems hard to think it would turn the entire top of the bale brownish/blackish from mold starting to settle due to condensation. Unless the bale was very damp to begin with and that is extremely unlikely in this case since it was at the top of the load and exposed to air. And again, it takes me back to the amount of time the tote is reported to have been there before PF/KK came and retrieved it. Not that long.
Either way, it's apparent the tote was in the barn and on that one particular hay bale. And a rubber tote with 100+lbs is a lot more than an empty rubber feeding bin or empty water bucket. So maybe it is possible that mold could have set in that early on..... but an entire top of a bale??? I pray it isn't seepage.... but mold.