Unlikely to be the problem. Boron deficiency has a completely different set of symptoms. Mostly noticed when it affects berries and young leaves:I notice that they didn't test Boron.
A vineyard that was so neglected from an inadequate spray schedule is far most likely then suffering from pest issues. Those grape vine leaf hoppers may certainly be a contributing factor. As may be fungus issues. Am leaning toward this not being a nutrient deficiency. If one grows susceptible varieties (ie. all Vinifera varieties) you have to spray appropriately for one pest or another. There is no way around it. It can not be neglected.The vines were neglected and only dusted a couple times with sulfur. I just started getting involved with managing the vineyard and creating an ipm program.