Quasi-job offer but nervous about sending transcript...

I interned in ECM last year as a rising sophomore and was invited back this year. I'm about to finish my internship and my group head took me out for lunch last week to say he thought that I've done a great job (notwithstanding my screwing up badly my third day) and that he thought I'd have a future at the firm.

Here's where it gets a little complicated: I had expressed interest in the past in a trading role (he had asked me at the time what other opportunities would interest me) and he wanted to know if that was still the case. He said that he'd be able to set up an informal meeting with my firm's head of Fixed Income trading, with whom he's good friends, and tell him that I'm extremely capable and he'd hire me right away but that he thought maybe I'd benefit from exposure to other parts of the firm. He added that he'd be able to (at least, hopefully) get me to the superday for a trading role. The good part is he said he'd be my "safety net" and that he'd just hire me into his group if I didn't get into the trading role.

My problem is that my transcript is garbage -- a sub-3.0 GPA, and I basically have every grade possible on it, from A+ to F. Even worse, the F is in a finance class (I'm an engineering major). Not that it's any excuse, but I had some very legit extracurriculars for two semesters that sucked up ~55 hours a week and a major, albeit undramatic, health issue one other semester (surgery and several days in the hospital under morphine two days before exam period first semester). I have a 2.8 GPA, but a 3.5 GPA in the three semesters I was healthy and only did 20hrs of extracurriculars a week. My boss knows my GPA is poor but I don't think he knows the extent (It was a 3.3 when I applied for the job a year ago and since I was invited back I never had to provide an updated resume, so it's not as if I've lied or misrepresented myself at any time.)

I'm worried that I won't get the trading role if I have to interview for it and that, even worse, my transcript is so bad that I won't even get hired back into my group. I'm wondering if anyone has any advice for when I meet with the head of trading to the end that he'd basically guarantee me a spot on the floor, and if anyone thinks it's possible I could not have that verbal offer in ECM convert to a real offer because of my transcipt.

Thanks for reading this -- I know it's long but I like to make sure all the relevant details are included.