Just to be sure: The arrow below is were the correct information is shown, in the invoice address. It is only when the pop-up opens when I click on invoice, that the incorrect address is shown. You probably got that, but just to be sure.
Then about cache: I do have cache enabled, but is is excluded for the Hikashop component using JotCache. Just to be sure, I disabled all cache (Jotcache + global config), and the problem is still there. Also, for the backend cache parameters should not m,atter, right?