I think it is hard decision, he wants badly to win RG and be ready for bigger events like Madrid and Rome for sure, but really no Nole at his own-family event, i wonder what people would say about it and how it can affect whole tournament, battle between Viktor and Janko for 250 title probably.
This is a big year for him. You can't please everyone if you want to be a true great. Federer is the master at organizing a tennis calender. Come to think of it I think Mirka does it for him. I doubt the Djoker's girlfriend knows anything about planning and organising a tennis season for someone .