Mulders chart shows a few things that lower copper uptake.
Manganese
Phosphorus
Iron
Nitrogen.
Magnesium can increase the uptake of the last 3 of those.
Only other thing I have heard about dynagro is a lot of people reporting it precipitating in the bottle.
This is a weird situation , you could check your water content out online, see if there is high iron content.
Or maybe its worth trying a different nutrient line for one crop ?
Flying blind here really.
But lets say if I was right about the tops been in a dead zone with no air flow and microclimates around the leaves, that could explain why your getting leaf temp readings higher than your expecting and possible suggest a cause of heat stress which in turn could cause them to lap up more N since plants will do that causing a whole bunch of other issues.
Lots of ifs buts and possibilities