tense related

[sane]

His classes were attended by other teachers, in addition to students, who were smart enough to have discovered (or “to discover”) him.

[Raymott]

His classes were attended by other teachers, in addition to students, who were smart enough to have discovered (or “to discover”) him.

You probably don't intend the meaning that the red comma places on the sentence.
"His classes were attended by students and other teachers who were smart enough to have discovered him."
That's my preference, but you could use either. No commas though.