modify host group in affinity/drs rules

Per my other thread I can now get a list of groups that my host is a member of but when I try my workflow to adding it back, my task errors out with: A specified parameter was not correct.

This is the code I'm using (adapted from powercli that was captured in vcenter) where:

myHost = VC:HostSystem

hostGroupName = string

var spec = new VcClusterConfigSpecEx();

var myArrayOfHosts = new Array();
myArrayOfHosts[0] = new VcHostSystem();
myArrayOfHosts[0] = myHost;

var myVcClusterHostGroup = new VcClusterHostGroup();
myVcClusterHostGroup.host = myArrayOfHosts;
myVcClusterHostGroup.name = hostGroupName;
myVcClusterHostGroup.userCreated = true;

var myVcClusterGroupSpec = new Array()
myVcClusterGroupSpec[0] = new VcClusterGroupSpec();
myVcClusterGroupSpec[0].operation = VcArrayUpdateOperation.add;
myVcClusterGroupSpec[0].info = new VcClusterHostGroup();
myVcClusterGroupSpec[0].info = myVcClusterHostGroup;

spec.groupSpec = myVcClusterGroupSpec;
spec.drsConfig = new VcClusterDrsConfigInfo();
myTask = myHost.parent.reconfigureComputeResource_Task(spec,true)

At one point I managed to get the task to go through (don't figure out what i changed anymore) but it didn't actually add the host to the group.

Any ideas as to the problem?