No Pope has made such claim, but he wouldn't need to.
As Hebrews says,
Long ago, at many times and in many ways, God spoke to our fathers by the prophets,
Just because one does not have a face to face encounter does not mean that God has not spoken to them. Very few of the prophets claim they saw God's face. Indeed, Elijah perceived him only as a "still small voice." Jeremiah saw the visions God intended for him, but none was a vision of God himself.
Indeed, Penuiel is a time where God deviated from his normal practice, in revealing himself. Later, when Moses sought to seek God's face (Exodus 33), it was understood he could not see God's face and live.
The lesson has less to do with whether or not God changes, then if man's ability to relate to God changes. And, to box God into a place where he cannot relate to people differently runs counter to his nature as a person who is capable of relating.
Futhermore, as God's appointed representative on earth, Catholics (and I am not one) claim on the basis of Matthew 18:18 that:
"Truly I say to you, whatever you bind on earth shall have been bound in heaven; and whatever you loose on earth shall have been loosed in heaven. Verily I say unto you, Whatsoever ye shall bind on earth shall be bound in heaven: and whatsoever ye shall loose on earth shall be loosed in heaven.
This translates into the ability for the Apostolic office (established with Peter to whom Jesus says this) to make heavenly decisions, under God's guidance, in accordance with God's wishes.