generally speaking toning works better if the original fixer DOESNOT have a hardener.
It has not been my experience with sepia or sepia types to use a hardener fixer after toning; however, i don't use kodak sepia toners.
There is a toning processes that does suggest post fixer with a hardener; Nelson's gold.

Some folks do use a hardener pre-toning when using Kodak Brown toner. I have not tested this method, but have done quite a bit of testing with KBT with prints that have been fixed with Ilford rapid fixer which does not have a hardener.

Kodak makes a liquid fixer that has a hardener then of course there is the version that has a separate container of hardener that is added .

I wouldn't worry .