Robbing in Fifty Degrees, at the end of October, Really??

I became an eyewitness to one of my worst fears in beekeeping, robbing. I seriously was so very, very careful to avoid this from happening. I noticed it on October 26 when I went to place my winter screen on the hive. This particular hive sits by itself more that 500 feet from five of my other hives. The reason for the different location is irrelevant. It was sunny and 58 degrees. As I walked up to it I noticed  a lot of activity and a louder buzzing than what would be normal. Honeybees and Yellow jackets were flying up the sides of the hive, hovering at the joints between boxes and trying to gain access under the telescoping cover.  This hive already had an entrance reducer on and was reduced to four small holes.  I had placed a queen excluder and top winter shell on Oct 20.(I use the exculder to set my winter sugar bricks on)  The top shell had a single small hole for a winter upper entrance and ventilation. Yellow Jackets and honeybees were pouring in and out of that hole. I grabbed a wad of grass and stuck it into the hole. I ran back to the van and grabbed my trusty  Duct Tape.  I wrapped the tape around the seams even though they weren't getting in there. I taped shut all but one entrance hole on the reducer at the lower entrance.  Then I stood back and just shook my head.
There wasn't much more I could do.  I do not have robbing screens nor did I have the materials to make one.  Later I spread Vicks Vapo Rub on the entrance.  I had read that it confuses the robbers and placed a screen in front of the hive entrance.
I checked the hive today and found Yellow jackets sauntering in and out of the single entrance hole uncontested.  They are just so wicked!  I waited till dusk to investigate the inside of the hive. In the pictures below you'll see I found only a handful of bees surrounded by wax cappings on the bottom board.  A very small amount of capped brood was in the lower hive body and on a brighter note I found about five frames of capped honey that the robbers had not gotten to yet in the top box.
From my notes, this hive appeared strong on September 17, lots of bees, enough honey for winter.  I did not do a thorough inspection on that day.  When I placed the winter shell (shallow box) the week before there were not many bees in the top box, but  I figured they were down in the bottom at this time of year. Soooooo, not quite sure what happened here. Was robbing alone to blame for its demise or had the majority of the colony already left and hence the robbers were able to gain access because it was so weak?
  I picked through the dead honey bees on the bottom board and did not find the queen. I did see evidence of Varroa mites.  A few  dead Varroa mites scattered among the cappings. This hive had a break in the brood cycle in July, but no chemical treatments for Varroa.  No evidence of small hive beetle or disease.

The sad sight when I removed the entrance reducer

The bottom board, dead honeybees, yellow jackets and wax cappings



The dead defenders.  If you zoom in you can see tiny red ovals among the cappings, those are dead  varroa mites, the Honeybees and beekeepers worst enemy.

Capped honey frames from the top box. I can add to  other hives for extra feed. 

You can see where the wax cappings were carelessly ripped away by the robbers to obtain the honey stored beneath.

A frame of partially capped brood and honey from the lower box. in top left corner you can see evidence of robbing. 

The hive that was robbed.  It is one at my off site.  Noticed it on October 26.  Not sure when it started.  More looters/robbers on other side of  the hive, I should've gotten a better picture of that. I plugged the upper entrance with grass. 

The other hives some five hundred feet away.  All precautions being taken to prevent the start of robbing in this yard. I can't believe I'm hoping for lower temperatures and some good hard frosts!