MFJ or single?

I just ran the numbers and it’s saying we owe $ either way which I feel can’t be right!! Ugh.

We are both on IBR. Husband: 53k student loans, income 66k. Me: 27k student loans, income $102k

If we file together or separate I will be paying the max for IBR which is 10 year plan cap about $300. Fine. But for him the cap would be like $600? We can’t afford that right now, have a lot of other expenses. So I was hoping filing separately would keep his loan closer to mine monthly. But so far it seems he owes over 2k if he files separately.

Any advice?