Why should the Central Powers act as if a ceasefire has already been agreed on when the Entente refuses to even reply in good faith to the negotiation attempt? You realize how utterly nonsensical your accusation is?
The offer itself was empty. Negotiations do not end with the terms put up in the beginning, but there must be something in it to show even a possibility of peace.
Its a negotiation, they didn't even bother to try and convince them to. After all the Entente would need to offer something to get the Germans to evacuate territory.
Not even Belgium, the country that they had themselves invaded was included for reparations by Germany.
Status quo for Germany with indemnities on France, the country that they had harmed. No compensation for the damage done is mentioned.
All that said, the sunk cost was so high that no negotiated peace would have been possible.