This might seem insignificant, but is he cleaning out what he's killing off? I don't know what Vaxa is, but I avoid factory-products now, so am out of that loop.
I would worry that a 76 year-old has many years of waste accumulated and to cleanse some of it out would ease the burden on the whole body.
I've noticed many people doing parasite cleanses don't seem concerned with the rest of their diets, but the average diet puts a strain on the elimination system.
I know you can only expect a person to do so much and it's better to make gradual changes most of the time, but maybe he could adopt some cleansing protocols to ease the burden on his body.