Return Offer in Non-banking Finance Internship at a Smaller Firm

I am a rising junior about to head into recruiting season for IB SA positions. I intern at a small-to-medium sized firm that is related to finance but is not banking. I am curious how important it is to get a return offer at a place like this for banking interviews. Will I be asked? Is it easy for a bank to find out for themselves one way or the other? It isn't that I plan on not working hard or something ridiculous like that, but I find myself panicking about getting a return offer at this firm from the moment I rise in the morning to when I go to sleep at night. I am looking for solid, honest guidance on this one. If anyone has any experience in this respect, please let me know.