So, I cleaned out the 10 gallon my 5 females were in, I moved all my guppies into another 10 gallon, and as I'm scooting the gravel vac around, this one piece of "stuff" rapidly scooted away. It was a fry!!! None of my females even looked pregnant! I haven't seen any more babies in any of the tanks since.
So, now the little booger is in a business card sized box with an airstone. Good thing I didn't throw away my Hikari "FirstBites".....At least water changes will be easy. It should be safe in there, a whole lot safer than in the 2.5 gallon tank with the wild guppy or in the 5 gallon with the betta and barb.