Here is an update on Mr. Wilcox. He is still alive but not walking. He will stand for maybe 15 minutes tops. His blood was retested and his high white blood cell count has dropped back to the normal range. So that's promising. His Marek's test came back negative (but the vet did warn me that a false negative is a possibility). He's eating and no longer lethargic. He's being treated for bumble foot now...which the vet thought was not very advanced.
But, hopefully, when that issue is dealt with and his feet are healed, I'll see some improvement. I'm thinking I may own the most expensive rooster in town. lol