It's early days here, this code was just released, we'll have to try again soon to see if the backing server it's checking for updates is operational. The error I'm getting on Jun 24 2020 is:
"Update 7.0.0.10400 is not found" in both vLCM and VAMI's update functions.
Meanwhile, have a look at release notes:
"VMware vCenter Server 7.0.0b Release Notes"
https://docs.vmware.com/en/VMware-vSp...
and see also:
"How to update any VMware ESXi Hypervisor to the latest using ESXCLI for easy download and install"
https://TinkerTry.com/easy-update-to-...