HU tournament, blinds are 50/100 with no ante, green 25 and black 100 chips are the smallest two denominations in play.

Button puts out 1 black chip as cards are being dealt, since he doesn't have any green chips in his stack. A few seconds after cards have been dealt, big blind sees the black chip sitting in front of the button, and, thinking it is a limp, raises to 350. Dealer announces "raise" and button mucks. Dealer then pushes entire pot to the big blind.

Button then protests that he deserves 50 chip change, that he never limped, it was only his small blind. Big blind contends he had no way to differentiate a small blind requiring change and a limp and that button folding after dealer announces "raise" without objecting to the apparent out of turn action means the button was folding to the raise and not open mucking.

Floor is called. Ruling?

If he really thought it was only his SB out there, why did he fold to the raise? He would know the action was still on himself. I don't give him change.

Say Button had put out 50 and, before he can act, his Opponent announces "Raise".
Button has junk.
You want Button to complain that the action is out of turn: make the Opponent take back his raise; then open muck?

You're fired.

SB folded without calling the BB. Give him his change.

This.

Maybe he didn't fold to the raise. Maybe he folded because he saw the BB raised OOT and he didn't want to call the big blind when he knows a raise is coming.

He gets his change back all day.

Because it's clearly impossible that BB pay attention to the one other player at the table.

This one is not even close. Where it starts to get more troublesome is if SB doesn't put out the chip until after the cards are dealt.

Change comin

That's rich!

Might sound a little far fetched or crazy, but I think he may be able to ask the dealer!