Absolutely zero chance he would have more than 4bill like golden boy Shanks (even if Shanks bounty increase prior)
Probably 3bill like all Admirals and old Garp (who was his equivalent main opponent at Hachinosu)
Lower than 3b is more possible than any 4b+ since he isn't a pirate/BB crew for that much long and doesn't cause much scene for WG as a threat for the time being.