Although I appreciate your argument, as a left back, he'd be more likely to be going if he was English. His competition would be Luke Shaw, Tyrick Mitchell and some out of position right backs. For Spain it's Jordi Alba, Marcos Alonso,Jose Gaya, Sergio Reguilon etc.
We bought Dan for an undisclosed fee in the region of £3.2 million and sold him, at the age of 29, with 7 months left on his contract, for about 4 times that. It gave the player the opportunity to play for his boyhood club and it was the decent thing to do for a good servant of the club...