I may be wrong but it looks like the problem font you reference may be in an image, is not text. Sometimes things that appear as header text and/or site style text are actually image files (e.g. .jpg) and, of course, there's no way to alter text in an mage.
Also, too, if you haven't already I suggest you take a look at APHont, a font developed by American Printing House for the Blind specifically for low vision readers. It helped me a lot when I had post-cataract surgery (aggravated by Fuchs Syndrome) issues. Good luck.
Thanks for directions me to APHont. Can it be used oh my pixel?