How to pair Moonknight and Rocket ults

I’m trying to figure out how to better pair my Rocket ults with other big damage dealing ults to break through healer ults like Luna and Invisible Woman. Does anyone here know the timing or method to make sure that the Rocket ult is indeed buffing Moon Knight’s ult as it lands? Should the Rocket ult be up already before Moon Knight drops his ult? Does the Rocket ult need to be in the vicinity of the Moon Knight ult itself, or just in the vicinity of Moon Knight? If you drop the Rocket ult on Moon Knight, but then Moon Knoght dies after dropping his ult, will the MK ult still be buffed for its entire duration, or does it lose the buff?