Hey Rober, since we found the entrance reducer moved or dropped off the bottom board, we now have the reducers down to the width of one bee. So it will be obvious if there is another rat. Today I'm going to shine a flash light in all the bottom boards to see if there is any rat poo or mischief left behind. If the bottom boards are clean then I won't crack open the hives.
Hubby disposed of live entombed rat several miles up into the woods, no where near housing, there won't be a prob for any other residence.
However, we have a couple rat snap traps set in the garage now, and one under the nucs just in case.