Hi,
What I learned in the way glusterfs works is you specify the host only to grab the initial volume information, then it'll go directly to the other hosts to connect to the datastore - this avoids the bottleneck issue that NFS has.
Knowing this, the work around I used was to setup keepalived on the gluster hosts (make sure you set it up on an interface other than your ovirtmgmt or you'll clash with the live migration components). So now if one of my hosts drop from the cluster, the storage access is not lost. I haven't fully tested the whole infrastructure yet but my only fear is they may drop into "PAUSE" mode during the keepalived transition period.
The other thing to note, is you've only got two gluster hosts. I believe by default now ovirt sets the quorum setting which enforces that there must be atleast 2 nodes alive in your configuration. This means when there is only 1 gluster server up, you'll be able to read but not write this is to avoid split-brain.