You are mixing up Cambridge & Oxford requirements. Oxford requires 3, not 5, APs and although the tutors prefer APs, subject tests are accepted.
As @Twoin18 pointed out, conditional offers are the norm, not the exception in the UK.
But: based on your other posts you have other issues, such as the ACt - in another post you say that you are hoping to get a. 29 on the ACT- Oxford requires a 32.