This is a really Interesting case.
Though I am truly sorry for your losses. There was a short time inbetween these two unfortunate deaths and I do have to attribute that to a variety of a couple things. I do think the internal temp of the rat could have effected things a bit, a cold spot would put the ball into shock because of the massive temp change in their bodies. I also think that because of the shock, the snake was frantic on regurging making aspiration more of a danger. I would get a necropsy done, I think that's the smartest thing to do. And I hope you find the answers you need.
I am sorry.

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