Hi Rhian,
Thank you for uploading your logs as it's really helpful.
When you provisioned the first VMmark tile, it appears that most of your VMmark VMs were created and pinged successfully, but some failed. (Privately, you mentioned that if you reran the deploy, the same failure occurred but on a different VM each time) To me, this implies you are seeing intermittent network issues in your environment.
Please check this forum post which had the same error: VMmark ERROR and config help
There are some recommendations there of how to check your network setup as well as how the user resolved the issue.
Thank you,
Rebecca