Why don't the links work in the Excel work book I emailed?

I created a workbook with 5 tabs. It is to track the hours my Habitat for Humanity “family” has put into their house, getting it ready to move in.
She sent me 4 different logs. I pulled them all together in the first tab, for a total of 100 hours logged between the 4 logs.
Tabs 2, 3, 4, and 5 have JPEG of the logs she took pictures of and sent to me.
Here is an example of the first log couple of logs listed:
Here

I have links to the tabs containing each log. I emailed this to my husband to be sure that the links would work…and they don’t. The tabs are there so you can manually click on the tab to see the log, so it sent the whole workbook, but the links on the first page to send you to the tabs don’t work.

Why not?