Yeah sure, but that's just speculation, the only Hamon we ever seen harm a Pillar Man, was Hamon the eclipses Jonathan's High 8-C Hamon (And even then, it was never lethal on its own, it need a bunch of attacks or internal attacks to do lasting damage), for all we know the Hamon needs to be an equal force to the Pillar men to break the skin (Which tbh might be the case). Joseph's Hamon might've been weaker, but it also did literally nothing.
We can't say Jonathan's Hamon would work for sure, best case, if it does work, it still wouldn't be lethal, it'd likely hurt and damage, but it won't like melt or effect the whole body, he'd need to land it internally or land multiple overdrives, and I just don't see that happening against any Pillar Men without Jonathan getting maimed in the process trying.
Sword won't work, unless he takes Santana off guard or Santana is already hurt, Santana can make his skin like rubber, nullifying a blade's piercing damage, he did so against Joseph when Joseph tried to stab him initially.
