Shouldn't be an issue as it is pretty far back.
What clamps are you using? If you are not using TorcTite exhaust clamps get them. I have used a breaker bar to tighten them and haven't broke one yet.
You can also use a copper exhaust spay sealer before you slip the pieces together and then clamp it with a TorcTite.
All in all I bet the carbon will fill the void after a bit though.
Your choice really as I don't see it causing an issue.