Oh you did just fine and it's understandable about the confusion. The fact that he got famous by doing the Lancelot role and singing the songs like "If Ever I Would Leave You" certainly did not preclude him from portraying King Arthur in later versions of the same play which he certainly did. I would have given my eyeteeth to see him doing either of these roles live and in person.
That being said, I am very appreciative of the fact that your link of him singing the song by far made me appreciate him now more than ever. He was one of the great singers on the American musical theater stage - make no bones about it.
Thank you, I’m glad you got some enjoyment out of it and if you look you will see that I changed the wording on the one image, lol.
It’s magic!!