Once metal heats and expands, it does a good job of closing caps where gaps shouldn’t be in the first place.
I would do a visual inspection of all the exhaust if you have access to a lift or a heated garage and good jack stands.
You could also use a rag to cover one exhaust pipe and see if you can see those exhaust gasses escaping somewhere else. Do not do this for a prolonged period of time though C8-)