Rodimer had to have known of the sexual abuse problem in his diocese for close to 20 years, as Pope Pius High School was closed in 1983 to pay a settlement in a sex-abuse case. You would think Rodimer would be a bit more aware of what was going on in his diocese after that happened.
And from the article: Rodimer had no knowledge of their relationship, and never asked about it.
I contend it is not normal to not make small talk about relationships with people using a vacation home. This was not benign ignorance, this was conscious avoidance, because Rodimer knew what the answers would be (or should be if Osinski were truthful)