Yes it should work. I can do HSS with cactus vii to rf60 and v6ii to RL600B (with another v6ii attached) HSS no problem. I even went as far as updating to the latest firmware for the xt2 and it works with no issues.
On another note, lenses are not like camera bodies. They hold their values. Maybe $100 off would be a killer deal but you're dreaming if you think you can get this lens in this condition for under $900.