<<Isn’t it behavior — not self-perception — that objectively defines one’s sexual orientation?>>

Absolutely not. Your quotation from John Jay (JJ) correctly asserts the exact opposite. Think about the prevalence of gay rape among straight prisoners. "Opportunity" is important.

Null, it is critical to distinguish pedophilia from ephebophilia among clerical abusers. We now know pedophilia is intractable, but ephebophilia behavior is more complex. Most non-pedophile sexual abusers, whether gay or straight, are best understood as sexually immature, sexually confused, sexually repressed, with "opportunity" for young boys. 

It is not homosexuality or heterosexuality that correlates, IMHO, with the selection of illegal targets, but immaturity, etc. 

BTW, I was unaware JJ estimated 5% to 50% gay clergy. IMHO, globally the correct figure today is minimally 50%, and perhaps as high as 75%. Reliable data is virtually impossible given the ongoing preference for the closet among priests.