I would still like you to try
"C:\Program Files\VMware\VMware Tools\vmtoolsd.exe" --cmd "info-get guestinfo.ovfEnv"
fromthe command line when the issue happens again. But I suspect that it will succeed.
I'm not 100% sure, but I believe "info-get guestinfo.ovfEnv" could be provided by some Tools plug-in called 'guestInfo'. So, the theory I have is that it might be some sort of race condition between 'guestInfo' and 'deployPkg' Tools plug-ins. I don't have exact confirmation, but by enabling Tools logging I can see some lines like:
[Feb 07 10:11:35.859] [ debug] [vmsvc] Unable to open 'C:\Program Files\VMware\VMware Tools\messages\en\deployPkg.vmsg': No such file or directory
...
[Feb 07 10:11:35.875] [ debug] [vmsvc] Unable to open 'C:\Program Files\VMware\VMware Tools\messages\en\guestInfo.vmsg': No such file or directory
It could be that 'deployPkg' gets loaded and executed before 'guestInfo' (or maybe it's some other part of Tools - but you get the idea) is fully ready. I think Tools plug-ins were ment to be very generic mechanism. Thus, I believe Tools won't provide any guarantee regarding ordering of the plug-ins. In which case it might be that simply retrying "info-get guestinfo.ovfEnv" after small timeout would make guest customization more robust and prevent the issue from happening.
I suggest that you open SR with this info.
/Andrii