Cylinder 6 misfire ??

It's possible.

Take the COPs out. Sop up as much of the liquid from the plug holes as you can. Then remove the plugs and clean them with a degreaser solvent. With the plugs out, make sure the wells are dry: Use a lint-free cloth down each one to dry the walls etc.

Inspect inside the COP boots, making sure they're all clean and dry. (You can actually replace just the boots and springs if need be...)

Re-assemble everything: Torque the plugs to 13 ft-lbs, use dielectric grease on the contacts and place the COPs back in. If the misfire continues on a given cylinder, swap the COP on that cylinder with one from another. If the problem follows the COP it needs replacing. If the problem stays with the original cylinder you've got other issues...