There isn't a possible way other than changing the datablock's max damage, but if you do that, it will bug. The only way to fix it is that the add-on has to be modified.
I am thinking of reviving the mod and adding a support for %player.getHealth() instead of using %player.getDatablock().maxDamage since that is a bad thing to do if there is a modification. If so, I could modify all the health add-ons to be stable with the health mod.