Or, when should I complete it? Long time Legion fans and players, I need your help!

I'm playing a DiD Legion character, and this quest in particular has left me scratching my head. On one hand, it's maybe one of the few (very, very few) Legion quests that I can complete before meeting Caesar and therefore before the NCR pardon. That would leave me vulnerable to the NCR hit squad for a shorter period overall and less likely to die horribly, while still having the nice Legion rep boost. Moreover, this would mean no veteran rangers nor power armored troopers in Forlorn Hope.

On the other hand, it's still an entire bloody NCR camp. Full of soldiers who can shoot me dead. And at this level, I kinda don't have the skills or the equipment to kill every officer silently, so it's pretty much me, Veronica and Rex storming the camp. Furthermore, do officers at McCarran know if you've done this, or do they just check your reputation? I'll need those guys on my side, if I want to do the infiltration missions.

To conclude, I have two kind of related questions:
1. Return To Sender: from a RP point of view, do you feel I should do this or not?
2. Do First Recon show up at Forlorn Hope if you have destroyed the camp and completed Three Card Bounty?

Many thanks in advance!