Yes, a week ago Sat
Eidelon was in the vault - not even fully upgraded (just to validate you do not need it with you or fully upgraded - in fact don't even need to own it or HOP)
I have a Necrochasm, so ist being dropping. Members in my clan have Crux's tht they dont even want too. I found it was not dropping for me either as I only got one about a week or two ago...funny thing is I tried something different......I pulled my eidolon(not sure if its spelled right) ally out of the vault and attached it to my warlock's inventory (not equipped) just in the character's inventory and upon completing Crota on hard, it finally dropped.....Not sure if it will wrk for you but worth a try...GL