Been away for a bit, just been catching up...........wow! amazing reading this thread, Mirror you're doing stonkingly well to manage the situation.
So we think the off license med has stopped her liver dumping, and she maybe producing some insulin? I'm not sure on that, I think the drop in blood sugar is kidney function (doing as they should - cleaning the blood) the drops aren't massive, insulin like drops. But at the same time small injected doseages of insulin cause a big drop so highly sensitive to the stuff!
Is she drinking and going to the loo a fair bit now it appears she's not had a hypo for a while? (especially that evening when she had the MaccyD)