Pope Alexander VII declared that passionate kissing, even when danger of further consent (fornication) was no there was still gravely illicit.
So the Church has spoken, dogmatically, that passionate kissing is gravely illicit and thus to engage in this behavior is mortally sinful. He condemned the idea that it was venial as heresy.
St. Alphonsus says (about this declaration)
“…this means that every time someone with sufficient reflection and full consent of the will delights in carnal or sensual pleasure associated with to whom he is not married he commits a mortal sin. This is not only true with kisses but also with respect to other touches performed for carnal pleasure. The reason is that any delight taken in carnal pleasure, that is to say any delight taken in stirring up the appetites which surround the creative power, is a movement towards the martial act.”
So those priests ARE WRONG and need to have prayers said on their behalf.