I managed to contact the fellow who ordered the parts for this bathroom sink and he then followed up on a replacement fitting. The new part should be here in a couple of days. I'll look then to find out the make and in the future make sure we spec all metal fittings if possible.
I would think saving $30-$50 on this fitting is a poor choice when a plumbing repair bill can be over $200.00 when a plastic part dries out and becomes brittle. I believe this is do to the plastercisers used in the manufacturing process.