I managed to find a rough workaround for this, and is as follows:
bool collapsedTable = false;
string relationshipTypeName = navProperty.RelationshipType.Name;
var assocSet = container.BaseEntitySets.OfType<AssociationSet>()
.Where(es => es.Name == relationshipTypeName && !es.ElementType.IsForeignKey)
.FirstOrDefault();
if (assocSet != null)
{
collapsedTable = true;
}
In case anyone hits a similar problem. It seems to fix the exact issue I was having...whether or not this is a 100% solution to it for 100% percent of cases, I am not sure. Any issues with it, and I will revisit.