As a side note, it's ridiculous that he CAN negotiate a lower amount once he gets to his club if he goes via Free Agency (see: Joe Daniher)As far as I've read, he can nominate for the ND, or say he wants to be held over to the PSD. If he nominates for the national draft, he has to set out the $ he wants (so whatever it is Geelong is offering) and he's bound to that club for 2 years.
If he's taking unders to go to Geelong, then obviously that means a higher chance someone else will take him. If he puts in a higher $, and Geelong takes him, he can't then sign for a lower amount once he gets to Geelong.