Getting the same "non-result" in all browsers other than IE strongly suggests to me that the site in question (or at least the part you're trying to work with) was written extensively using IE HTML extensions. If that's the case, while you may get different results with JAWS, it will probably not be satisfactory, either, particularly if you're using an up-to-date version.
If that's the case, and the company in question cares about accessibility, they're going to have to review that code and eliminate non-standard HTML extensions.
Brian - Windows 10 Pro, 64-Bit, Version 1809, Build 17763
Growth for the sake of growth is the ideology of the cancer cell.
~ Edward Abbey