Well, I do not think it will be much of a problem. My aunt booked 3 tickets with a travel agent, and the agent mistakenly entered all middle names as first names for her kids. Example will be Peter Stanley Foster showed up just as Stanley Foster. Called AA, as well as asked AA airport agents, and all of them said the name should be fine, as it is "part" of their names. I even brought the kids' passports to the airport with me. I said: Isn't it needs to be exactly like the passport name? I asked them 3 times whether they are sure it is fine, since they are going abroad, and 3 times I got the answer "yes". They eventually went on the plane without an issue.