is Cipher Trace merely saying they lost the funds after they hit the mixing service?
Yes.
ChipMixer chip creation and Wasabi CoinJoin are distinct and easy to recognize.
If you spot Wasabi CoinJoin - you know that [simplified] owner of one of inputs is owner of one of outputs.
If you spot ChipMixer chip creation - you know that owner of one of inputs is owner of some of chips - created in the past or in the future.