Chance on the other hand, was happy when Edwin chimed in and insisted Carol to agree with this idea. This was a confirmation for Chance that this guy indeed has no idea who Grim Reaper is and wishes to meet all Lucas' friends to figure this out.
With the information Bill provided him, Chance started thinking like Edwin. He placed himself in Edwin's shoes and thought what he would do and seeing how he was with Carol, Chance deduced that Edwin is using Carol to meet with her friends in the hope of coming across the Grim Reaper.
Therefore, Chance intentionally focused on inviting Lucas' friends to the party they will throw to observe Edwin's reaction, and as expected Edwin fell in his trap.
David looked at Chance in confusion as this party was something they never discussed before but when he saw the glow on Chance's face, he realized he was laying a trap for Edwin, so he too decided to support him.