The 600 playlist strike kills on my solstice hood (majestic) are just not progressing whatsoever. I did strikes with friends, on my own, and restarted a few times. It doesn't seem to want to work. I made sure the armor was equipped. The 300 solar orbs in playlist strikes even progressed all the way for the majestic boots at this point, so I don't think I'm mistaken. I tried to look up a guide to see if the symbol meant rocket launcher kills or disintegration kills or something but everything I found said it was just playlist strike kills. I haven't seen this mentioned anywhere yet so I figured I'd leave this here.