How do I not make this awkward?

[MMSe]

short version:

Is it awkward to call guys from a fraternity up and ask if they can hang out or grab lunch if I only met them exactly one time, for 30 minutes? If I was IN the pledge class it wouldn't be, but I'm not, which makes me nervous, and I'm afraid they'll be too focused on their pledge class.

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Long version:

Rush ended up going quite badly for me. Actually it was probably the worst possible outcome.

I rushed one fraternity that I liked a lot, but was rejected before their first invite-only night. At the same time, I was rushing a "backup" fraternity which I kind of liked, but had some reservations about.

Anyway, I was planning on deferring a bid from this backup because I kind of liked some of the guys in there a lot, but others....not so much and I had some reservations about the group as a whole. So I thought, "I'll just defer and hang out with them in the meantime and see how I feel after a while."

Which sucks is that on the very last day of rush, where it was invite only, I met 4-5 guys from a 3rd fraternity I hadn't considered before, and I ended up liking them all a lot. We ate lunch and as I learned more about their fraternity, I got really excited about it and started to get a better gut feeling than I did with my first backup.

So after lunch they said they'd give me a call later in the day, and I thought I might be lucky enough to get invited to their final invite-only night. But because I didn't meet with them until the last day of rush, the rush chair had to call me up and tell me that although I was a cool guy and "we should hang out sometime", they had a large pledge class and had to focus on the guys that attended the earlier events.

Needless to say, I was quite upset, and then I was even more upset when original backup called me and offered me a bid. And since I felt like my "heart" was with another fraternity now, I had to reject their bid and not defer it because I felt it'd be unfair to the brothers when I'd secretly be hanging out/wanting to hang out with other fraternity I just met. But the rush chair of this backup (who I like) asked me to attend their chapter meeting this afternoon just to see how they operate, so I'm going to go to be polite but it's going to be really painful.


So two questions:

1) Is it awkward to call guys from a fraternity up and ask if they can hang out or grab lunch sometime after I only met them once, for 30 minutes? If I was IN the pledge class it wouldn't be, but I'm not, which makes me nervous.
And I really want to get to know them better because I'm basically sacrificing my backup for them, but I know most of them will probably be assigned littles and will be busy with their pledge class and I don't want to appear awkward or desperate. So maybe I should give them a week or so? And they did technically reject me, but I feel I wouldn't have been if I had attended any of their 3 open house events OR their first invite only night.

and

2) Should I really feel guilty for rejecting this backup frat when, even though they like me, I just don't think I could take their membership vows with a whole heart? It really sucks because I've had a hard time making friends here overall, I'm lonely a lot, and this would be a really easy way out, but it would kind of be like I'm settling and I think that'd be unfair to them.