Been pushing pieces around on my board for a good hour & I've come around to the idea that white can win this but not in the middle of the board & only from one starting position.
If black makes the mistake of landing on c6 when white's king is on e4, then white has to set off up the h-file & it will arrive at h6 before black can stop it. Then it captures the f6 pawn & is able to promote the f5 pawn a full 2 moves ahead of black (or at least one).
If black goes after white's f4 pawn instead, then white can use the a5 pawn move at the last moment to switch tempo from black & still capture the f6 pawn.
If the two kings remain in the middle, then it's a draw.
Here's my poor attempt at a diagram:-
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It all depends on which square the black king is sitting: c6 & black loses the game but d6 & it can force a draw. The critical square for white to reach is h6.
You're right, and good catch - mimicking doesn't entirely work for white, since white isn't playing to draw. White needs to wait for the right opportunity to break the mimickry.
After 3...Kf7, white can play 4. Ke2 and 5. Kd3 no matter what black does, since as other people pointed out, black needs to answer Kd4 with ...Kc6 and Ke4 with ...Kd6.
After 5. Kd3:
EDIT: And yes, 3. Kd2 is also a good time to break the mimickry since you can answer 3...Kd6 with 4. Ke2! or 3...Kd7 with 4. Ke3!, preserving the zugzwang.