I can confirm that installing that cert manually fixed my issue. I am able to get imagery in my packaged game now.
Refer to this post for more guidance: KNOWN ISSUE: Tilesets not loading in packaged Unreal apps - #16 by ZenithEdge
I did a windows update but that didnt give me the cert, so I had to grab it from here:
Amazon Trust Services Repository
Not sure if I am allowed to post the link, please let me know and I will delete.