Because it's currently banned to do any deals with Qatar. The UAE & several countries have shunned them for want of a better word & all agreed not to do ANY dealings with the country or Qatari owned business. Etihad as example have refused to fly there.
It doesn't matter much. The business will be conducted between two European entities (regardless of ownership). Also, us Arabs (i'm from the ME) are known to put differences aside when it comes to making a deal.
Put your feelings aside, it might be time for Aguero to go. Ideally, it would be after next season - he'll become our top scorer.
Pep wants a team in his own mold, he will get one.