I tried my Rimowa IATA Spinner in the new UA sizers this week for the first time. The sizers are a bit oversized, as has been documented. My Rimowa fit well. It appears to pass, although if the GA got down on his/her hands and knees, they may be able to say it was over on width by a millimeter or so.

It is over the 14", but is likely to pass unless the GA is looking for a reason to give you trouble.