Zaire River Ferry Question - LSJ

My question is this, if i attach Zaire River Ferry on Moncada, whom i already attached a Cathedral San Nicholas, and another methuselah's minion plays bum rush and i cancel with the Zaire Rover Ferry by tapping and burning it, "what happens?" 
Does the methuselas still pay the 2 pool for the attempted action despite it being cancelled? I was thinking he might have to, considering the minion still stays tapped and doesnt get to play another action despite the cancellation.

"San Nicolás de los Servitas"

And, no, the cost of actions is not paid until and unless the action is successful.

yes, of course me bad...for misspelling that.
But just reconfirming, I thought Moncada's text was "[Other Methuselahs' actions targeting] Monçada cost an additional pool" and San Ncolas de los Servitas as saying "Actions directed at this Lasombra cost an additional pool".  They dont seem to imply that the action has to be successful for the additional pool costs, so if i blocked a bum's rush directed against a Moncada with San Nicolas with another minion he would still pay 2 pool right?

While it is true that the texts indicate that the cost of the action is increased, it is also true that the cost of an action is paid only when and if the action is successful.

Ok, thanks once again.  Guess we've played that wrong before.  We always thought of it as a cost for the targeting and not the cost of the action.  We will change accordingly.

Last question on a different but somewhat related topic, so if a minion has seeds of corruption and he attempts to remove a counter or attempts any other action for that matter, but gets blocked he doesnt burn any blood?

Unlike Zaire River Ferry (which increases the cost of the action), Seeds of Corruption provides text that causes the acting vampire to burn blood "when attempting an action". 

The current card text is: " Put this card on one of your prey's vampires. If the vampire is a Follower of Set, he or she burns 2 additional blood <when attempting an action>; otherwise, he or she burns 1 additional blood <when attempting an action>. ..."

And there's an old ruling from LSJ from 1997:

The vampire burns blood for Seeds of Corruption when the action is attempted. [LSJ 19971013]

So you declare the action, wait for it to be cancelled (e.g. Direct Intervention on an action card), then burn the blood for attempting the action.  (That is, the blood isn't burned if the action is cancelled immediately.) 

The upshot of this is that if a vampire has zero blood and Seeds of Corruption and they hunt successfully, they end up on 1 blood.  Hunt action declared, burn however much blood (and stay on zero), action successful, gain a blood.