Considering to sell him does not mean you can not train him.
It is true that pure inside skilled centers are not that rare and dont sell for much because of their high salaries.
It is also true that his B skills are not that good and will take a long time to train.
On the other side, your own draftees will get you a bonus in merchandise if the play an important role within your team so if you have a slot for a high salary Center in your team a trained draftee is the best choice.
Its not a matter of trust, ist a matter of choice:
1. difficult and time consuming training to get a good PF/C
2. get you own 4 skill monster with some passing
3. sell and look for an easier trainee