You do need to be a jr member on bitcointalk and have their signature in your account in order to benefit from the airdrop:
> In order to qualify, you must be a member of bitcointalk.org, at least at Jr Member level. You must wear DeepOnion signature during the course of all airdrops.
That said, bircointalk just changed the game yesterday and removed signatures for JR members. The good news is that the deeponion team running the airdrop quickly addressed that and said as long as the code is in your bitcointalk account, its good enough even if it doesn't show:
https://deeponion.org/community/threads/bitcointalk-jr-members-can-still-apply-for-airdrops.27417/Note the other requirements including a minimum number of onions in your wallet, participation on their forum etc.
If you have the time and interest, their bounties are legit.
Don't forget when someone really helps to thank by giving merit.