Cloning a template network connections set to E1000 instead of VMXNET3

I am using Orchestrator with the vCloud Director Plugin.  All of our products are current release of 5.1 and our vm's are using the latest virtual hardware.

I have catalog items created with a single nic.  That nic is set to VMXNET3.

If I deploy one of those catalog items in the vCD gui the resulting vApp vms will have the nic type set correctly to VMXNET3.  If I use a workflow the resulting nic's are always set to E1000.  Here is a snippet of the javascript from the workflow.  Most of the scriptable objects match up with what is in the API so it should look somewhat familiar.  This adds a template vm to an existing vApp:

var recomposeVAppParams = new VclRecomposeVAppParams();
var vmItem = new VclSourcedCompositionItemParam();
vmItem.source = vmTemplate.getReference();
vmItem.sourceDelete = false;
vmItem.instantiationParams = new VclInstantiationParams();

var networkConnectionSection = vmTemplate.getNetworkConnectionSection();

vmItem.instantiationParams.section.add(networkConnectionSection);
recomposeVAppParams.sourcedItem.add(vmItem);
return vApp.recompose(recomposeVAppParams);

Am I missing somethign or doing something incorrectly and vCD is just going with the most universal option by default?  Have I hit a bug of some sort?