Considering his passive is no longer a global that means if this is true it's way broken. His new passive only grants him a chance to gain extra gold.
Edit to add a question:
Were you using a jungle item like Wriggle's Lantern? 
Oh god. Are you sure the double is applying to the large ones as well? If so, that is scary broken. Hypercarry farm jungle inbound with "support" midlane TF.
Yeah... I don't want to assume you're being dumb, but Occam's Razor and all... Feral Flare line gives extra gold on every monster. Other Jungle items give extra gold based on how long it's been since you killed a monster. TF's passive is like, 1-6 gold or something, nowhere near double.
