They weren't surprised at all by the lawsuit. They wanted a lawsuit. The only person who could change the TOS was a judge and Epic could only sue if Apple enforced the TOS on them.

Plus, if you don't think Epic had already talked to lawyers and lobbyists in Washington DC and already been given a heads-up that they might win, then you don't know business that well.

They were well prepared for this, with what must've taken months of planning. They added the payment option, got banned, filed the lawsuit and published their 1984 parody ad, all within 24 hours.