1. that's precisely the issue: VMs in Manual setting do not shut down or power off on host reboot/shutdown. They crash when the host goes down.
2. manual shutdown (through Shut down Guest) by VMware tools works.
Funny thing I just observed: I also have a non-running VM in manual setting, which generates an error upon host shutdown: not supported in the current in the current power state (Powered off).
Log shows no attempt to shutdown the running VM in manual list.
I just tested shutting down the VM in manual list first, and got the same events: running VM in Auto list shuts down, then an error message because it cannot stop the other powered off VM, and then it continues.
There is no attempt to stop the second (normally running) VM in manual list.
So it looks like the error on stopping the first, powered off VM, interrupts the VM shutdown process, and makes the host go down before finishing VM shutdown.