Really block 50 should be using sniper if it has jhmcs. Should also be able to slave ir missiles to sniper afaik. Not 100% but im pretty sure you should be able to slave the mavs to the hmd like you can on the a10c as well.
Considering this was the one feature that is explicitly removed on export TGPs(e.g. AN/AAQ-19 Sharpshooter), its almost certain that it is possible, at least indirectly via slewing to markpoints.
