Can't connect to Electrs over Clearnet/HTTPS

I’ve got another server at home running Nginx Proxy Manager so I figured I’d use my VPS tunnel that I’m already using to expose some other services to the internet, to expose Electrs conveniently over Clearnet.

Request flow goes something like:
Internet > Cloudflare DNS (proxied) > VPS > [WireGuard tunnel] > Nginx Proxy Manager at home* > Umbrel

*SSL termination happens here

When I point e.g. BlueWallet at umbrel.local:50001 everything works fine. But when I point it at electrs.mydomain.com (SSL enabled), it can’t connect. I think I’m doing something wrong with my reverse proxy, or maybe this method of connecting to Electrs simply doesn’t work? I feel like I’m missing something… hopefully this is an easy one for someone to answer who knows more about the protocol than me.

TIA!