UPDATE: I am able to pull datastore information using the VI client and PowerCLI from all servers of our servers. I do not know what method your tests are using however, so I am not sure if that infor ...
I spoke with my boss and he wants me to try a few additional steps. I will let you know how it goes. Please let me know if you come across any information as well.
Im not sure if this is a bug in HM or VMware, but we have several "VM host free datastore" test results coming in as "Invalid Datastore counters". We are running HM 9.86 and ESXi 5 ...