ejabberd will not start

Files are missing in the ejabberd build. So it will no longer start. Installed from build service.
and erlang-erts is not available, even though the devel package is.

Is there some reason why you’re not downloading and trying to install packages directly from ejabberd?

Don’t know about the Linux 64-bits installer, from the documentation it sounds like it installs from a tar, plus walks you through initial configuration.
The RPM installer might work, depending on how it’s written. Of course if this works, then your install can be managed by zypper and YaST.

Instructions for installation

The Project source page which can of course also be a hint for what dependencies you might need

For your specific error,
You need the Erlang OTP runtime environment(which provides erts support) which I assume should be provided by installing Erlang (although OTP is not in the package’s description)

If simply installing Erlang isn’t sufficient for some reason,
Then the Erlang OTP source is available

With build instructions available in a number of places (should also generally be in source)