Gotcha.  Played with it for a while and used tblVmwareGuest.GuestFullName instead and here's what I ended up with
Select Top 1000000 tblAssets.AssetID,
  tblAssets.AssetName,
  tsysAssetTypes.AssetTypeIcon10 As icon,
  tblAssets.NrProcessors As [Socket Count],
  tblVmwareInfo.numCpuCores As [Core Count],
  Count.count As [Win Guest Count],
  tblAssets.Processor As [CPU Model],
  tblVmwareInfo.BiosVersion,
  tblAssets.Memory As RAM,
  tblVmwareInfo.Version As [ESXi Version],
  tblAssetCustom.Model,
  tblAssetCustom.Serialnumber As [Service Tag],
  tblAssetCustom.Warrantydate As [Warranty Expiration]
From tblAssets
  Left Join (Select Distinct Top 1000000 Count(tblAssets.AssetID) As count,
        tblAssets1.AssetName As Host,
        tblVmwareGuest.GuestFullName
      From tblAssets
        Inner Join tblVmwareGuest On tblAssets.AssetID = tblVmwareGuest.AssetID
        Inner Join tsysAssetTypes On tsysAssetTypes.AssetType =
          tblAssets.Assettype
        Inner Join tblAssetCustom On tblAssets.AssetID = tblAssetCustom.AssetID
        Inner Join tblState On tblState.State = tblAssetCustom.State
        Left Join tblVmwareInfo On tblVmwareGuest.HostID =
          tblVmwareInfo.VmwareID
        Left Join tblAssets tblAssets1 On tblAssets1.AssetID =
          tblVmwareInfo.AssetID
        Left Join tblVmwareVcenters On
          tblAssets.AssetID = tblVmwareVcenters.AssetID And tblAssets1.AssetID =
          tblVmwareVcenters.AssetID
      Where tblVmwareGuest.GuestFullName Like '%indows%'
      Group By tblAssets1.AssetName,
        tblVmwareGuest.GuestFullName) As Count On
    Count.Host = tblAssets.AssetName
  Inner Join tblAssetCustom On tblAssets.AssetID = tblAssetCustom.AssetID
  Inner Join tsysAssetTypes On tsysAssetTypes.AssetType = tblAssets.Assettype
  Left Join tblVmwareInfo On tblAssets.AssetID = tblVmwareInfo.AssetID
Where tsysAssetTypes.AssetTypename Like '%ESXi%Server%'
Still trying to figure out how to get your original subquery in there as a second column but this is the information I needed for now.
Thanks!!