I would seriously question it being any sort of Calamagrostis. That is a very upright grass and the bloom spike is not very comparable.

Unless it has received an excess of fertilizer....which I would doubt :-)

the bloom and plant do look something like Calamagrostis brachytricha, but that grass would not bloom until fall.

Thanks for validating my suspicions - a shame that a retailer/contractor would mislabel those but people make mistakes - just glad I caught this sooner than later.