Yikes, that was an expensive test! Another reason for a back up human meter.
Meters in the US can vary up to 20%. The 440, 402, 440 were practically the same number. 500 is within 20% of 440 and 387 is in there too. Thankfully the numbers will be much closer in lower numbers where it counts. And in all practicality, all those numbers just mean her blood sugar is too high. We are looking for general trends, and the exact numbers don't really matter when the blood sugar is so high.
Out of curiosity, when are you feeding Jade now? Yesterday from +2 to +3 she had biggish drop that could have set off a bounce. Giving her some food around +2 might give her some fresh carbs on board when she onsets, and slow down those drops.