I have the same problem and it got resolved now.
To resolve the initial issue we followed the steps in the following KB article https://kb.vmware.com/kb/56469.
Next we noticed that in event viewer we could see httpsproxy failing.
We extracted the files from the openSSL MSI file on the vCenter ISO and copied them into the vCenter directory, httpsproxy stopped failing and all the services started.
We then rebooted the vCenter to ensure all was ok and it came back up on the updated version without any issues.
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Extracted the files from the openSSL MSI file on the vCenter ISO using 7zip and copied them into the vcenter directory (Path: c$\Program Files\VMware\vCenter Server\openSSL)