Thanks for your help again @garethw .
When i tested using your commands – it was hitting the local DNS server (on the client side). So I dug a bit deeper to see what mistake I was making and sure enough I found the issue.
I was using homevpn.domain1.com as the Remote Server in the VPN client configuration as I had set up the A record in my public DNS account. However, the minute I added the domain override under Unbound for domain1.com, the VPN connection would not be initialized – as it would try to contact the VPN server side DNS (without the VPN connection being established)
In any case, I own 2 domains. So I ended up creating a new A record for homevpn.domain2.com and now use that for DDNS and as the vpn server endpoint. Then I added a domain override for domain1.com under Unbound and now I am able to access my self-hosted services via https from the client machine
Thanks again.