Timeless decision agents reply as if controlling all similar decision processes, including all copies of themselves. Classical causal decision agents, to reply "Yes" as a group, will need to somehow work out that other copies of themselves reply "Yes", and then reply "Yes" themselves. We can try to help out the causal decision agents on their coordination problem by supplying rules such as "If conflicting answers are delivered, everyone loses $50". If causal decision agents can win on the problem "If everyone says 'Yes' you all get $10, if everyone says 'No' you all lose $5, if there are conflicting answers you all lose $50" then they can presumably handle this. If not, then ultimately, I decline to be responsible for the stupidity of causal decision agents.

The coordination hack to work around some of the stupidity of causal decision agents doesn't appear to be necessary here.

"Somehow working out that the other copies of themselves reply 'yes'" should be trivial for an agent focussed on causality when the copies are identical, have no incentive to randomise and have identical inputs. If the payoff for others disagreeing is identical to the payoff for 'no' they can be ignored. The conflict penalty makes the coordination problem more difficult for the causal agent in this context, not less.