Dot Leader in TOC not showing up on EPUB Readers

My EPUB doesn't show the 'dot leader' in my TOC although it is in the InDesign document.

I have created a TOC Style.   I created a TOC Entry paragarph style with a right aligned tab and 'dot' leader between the TOC entry and the page number.   I selected this in the TOC Style Box and applied it to the Paragraph Style that relates to the items I want listed.

In the TOC Style dialogue box I selected Page Number After Entry, and for Between the Entry and Number I selected Right Indent Tab.

In the InDesign TOC it appears correctly with a dot leader, but in the EPUB there is only blank space between the TOC Entry and the page number. (Viewing it with Thorium Reader as well as Adobe Digital Editions).

I have spent about 3 hours playing around with anything and everything and it will not show up.  Does anyone experienced this and have any suggestions?