Having problems installing hass.io on ESXi - failed command: WRITE DMA

I’m trying to install hass.io on an Dell Optiplex ESXi 6.50 host. I’m using haos_ova-6.5.vmdk. I have been following this guide:
Hass.io on VMWare ESXi 6.7 - Step By Step
When I powered up I got a “failed to start grow file system” error, and it results in an endless loop of errors relating to DMA writes:



It is attempting thick provisioning of 115GB for the HDD, but there is only 118GB remaining on the physical storage drive. I don’t see any way of reducing that size in the config.
This is how my config looks:


Any ideas for how I can progress this?

Edit: so I just freed up another 100GB on the physical drive but it’s still failing with endless WRITE DMA failures :0(