The 28-year old former Manchester City, Southampton and Charlton Athletic striker joined the Red Bulls recently but is ineligible to play, however, Petke wants his visa sorted in time for the weekend's clash with Columbus Crew.
"We're hoping he can get visa this week," said Petke.
"They're going through some loopholes. The quicker we have him, the happier I'll be. It will most likely involve a trip to London.
"If it doesn't happen in the next 24 hours, then we're not looking for him at for Columbus."