@SorenJohnson, the issue seems to be interface scaling. If you scale the interface up past a certain point (I think I was three increments past the middle of the slider bar?), the Heal option is pushed offscreen for a unit with a Hero general. But unlike the Worker’s panel which has a scroll bar to access all his options, there was no way to scroll up to the unit’s Heal option. I was able to barely reach the border of the command with my mouse, and I was only able to tell it was the Heal button by the tooltip.
It’s not really an issue and I was able to fix the issue by scaling the interface back down.