Brand new players with high levels?

[nikolgiorgos]

He isn't a new player. You can't start from lv 7 and even if it was possible, it would be much harder (without enough money, facilities, fans or sources).
A possible scenario I can think is that he was playing as a guest (from his mobile device) and then connected his team with a fb account.

[Jeeves]

He isn't a new player...

That's right - he can't level up faster than once per season. You must be seeing a wrong founded date. Either a visual glitch, or like nikolgiorgos suggested the Manager probably linked to Facebook, or came back after being inactive, on the date you are seeing.