Safety Gerald Sensabaugh and center Andre Gurode also were considered questionable.
"We're going to wait until the last minute on all of those guys," Phillips said. "They haven't gotten a lot better. You don't want to play with an injured player and those guys are all injured. They haven't gotten to the point where it looks like they're going to be ready, (but) we're not going to declare today that they're out."
The Cowboys (2-2) play at Kansas City (0-4) Sunday.
Jones has a knee sprain, Williams a rib injury, Sensabaugh a thumb injury and Gurode a knee problem.