The Irish Derby winner is the big-name Ballydoyle entry from seven possible runners from the O'Brien yard, but he might now head straight for the William Hill St Leger at Doncaster on September 16.
O'Brien said: "Capri may not go for the Voltigeur.
"He didn't have a clean scope this morning, and we'll see how he is tomorrow.
"Usually if it's not clean today it won't be tomorrow, so we'll see.
"If he doesn't make York then he'll go straight to Doncaster.
"Venice Beach, Douglas Macarthur and maybe one other could go for the Voltigeur."
O'Brien could also be represented in the Group Two at York by Exemplar, Finn McCool, Spanish Steps and Taj Mahal."
Betway were as short as 4-1 about Capri for the Great Voltigeur on Sunday morning but following the news Paddy Power are now as big as 10-1. Cracksman is the 6-4 favourite.