I contacted Dr. Couto a couple of years ago after Loca was diagnosed with chondrosarcoma. All contact was via email (he replied to my initial email within hours). My vet sent him Loca's x-rays, but I'll bet you could do it, also. His team definitely looked at them as they discovered that Loca was misdiagnosed and what the local radiologist interpreted as bone cancer was actually normal lung super-imposed on her collar bone. Incredibly, his consultations were free of charge.
If he needs any further info from you, he'll tell you. He'll let you know exactly what you need to do. Loca's info was sent from Canada and it wasn't an issue.
Please do contact him. He's an absolutely incredible person and will really help a lot. Even if it Lenny's diagnosis was accurate, once you've received consultation from Dr. Couto, you'll have no reason to ever doubt the diagnosis or your future decisions.
good luck and keep us posted!