Who's the baby daddy??

So I was with two different people a day apart. One of them I was hooking up with for 3 months and the other was a one time thing. The one time thing guy had a vasectomy. I am pregnant and the conception date could be either guy. I told the one without the vasectomy it was his but is there a possibility it could be the other guys?

Edit** yes I am 100% sure he had a vasectomy. The vasectomy guy knows nothing about the baby. I thought the whole time it was tje other guys but then I got scared 😨

NEW EDIT***

The guy who is most likely the father wants absolutely nothing to do with the child at all. I talked with Vasectomy guy and he got it done 4 years ago which scares me a little.