Hi EricinIT,
We are experiencing exactly the same issue with UAG 3.6 and Horizon 7.9 (please note that your setup, UAG 3.6 and Horizon 7.8, is not a supported configuration). We also use a wildcard certificate from GoDaddy. On Windows clients and the IOS App, the certificate seems valid, on the Android App and Igel thin clients the same certificate seems invalid. The same certificate worked fine on any configurations before the migration to UAG. I have submitted a ticket about this issue with VMware and can keep you informed of their response.
KInd regards,
Raymond