Extending graduation as a senior

I am hoping to get some advice since I am in a tough position at the moment. I am a senior at a non-target school in the southwest. I have a major in Finance & a minor in Real Estate with a 3.7/4 GPA. I was able to secure an internship with GS in their SLC office as part of their IB team there and I received a full time offer. Due to the location and the fact that I would've been working remotely, I turned the offer down to pursue RE development. Recently, I have been reconsidering my career path and I want to make the move back into banking, preferably into a real estate focused group. Since it is too late to apply for SA & FT positions, I am thinking of pursuing a MSF or delaying graduation by adding a second major. Do you think either of those options are a good idea to increase my chances to make it into banking at a large BB? If not, what other options would you recommend? Any input would be really appreciated!