I suspect Charlie didn't make the under 21's as he was barely out of non-league at that date and had already turned 21 when he departed from League 1 Swindon.
Yeah, I know, which is why I said like CA. You can have players over 21 playing for the U 21's.
You need to look back no further than 2009 Euros, when England got to the Euros final and were stuffed by the Hun. The Hun side then formed a fair bit of 14 WC winning side.
Germany U21: Neuer, Beck, Howedes, Boateng, Boenisch, Hummels (Aogo 83), Johnson (Schwaab 68), Castro, Khedira, Ozil (Schmelzer 89), Wagner.
Subs Not Used: Fromlowitz, Ebert, Marin, Grote, Adlung, Ben-Hatira, Ede, Sippel.
Goals: Castro 23, Ozil 48, Wagner 79, 84.
Booked: Boenisch, Wagner.
England U21: Loach, Cranie (Gardner 80), Richards, Onuoha (Mancienne 46), Gibbs, Cattermole, Muamba (Rodwell 77), Noble, Milner, Walcott, Johnson.
Subs Not Used: Lewis, Taylor, Stearman, Tomkins, Driver, Rose.
Of the England side several have had good Prem careers and will have very nice bank balances, but none have really gone on to show international quality, and Johnson is presently at HM Pleasure, we'll never know how Fabrice Muamba would have turned out.