I, uh, amazingly got into grad school twice without having to send in a writing sample, and to get into my History Ph.D program,sent in a material culture paper arguing the while the furnishings on steamboats reflected a cultureal norm, they clung to that cultural norm to help diffuse tensions people had about using new transportation technology. I also don't have a history BA. In fact I have a Public History MA, and part of an archaeology MA, and a BA in anthropology. You can totally get into an MA program without writing a history paper.

The thing is, if you hate your thesis, if you aren't interested in it, you're so much less likely to finish or produce a good piece. I say this a person who has an unfinished archaeology thesis to back me up. Go talk to your Bootcamp prof. They are there to help you, and I promise you, this is an issue they should be well equipped to handle.