[@Liotrent]
Probably both - Near the end of the war, Nick was pretty high rank since he spent most of his life in the military, and Robin's reputation most likely reached him. After all, beating a Mark lll is pretty impressive. They may have shared a battlefield near the end of the war, since both were in service until it ended, but considering the vast difference in their fighting roles (Heavy artillery support and light 'hit-and-run'), they probably never met directly, unless it was off the field.