No.

Simple logic: The defacement was amature at best. If the group has a 0-day in a hypervisor they would have gone to multiple hosting companies and multiple attacks would have taken place, there are many more targets that are worth much more than openSSL.

Most likely, the administration panel of the hosting company was comprimised through malware/phishing. Seriously, if a group like this had a 0-day in hypervisor then they would be doing much much more damage.