Uniates?
“Whoever transgresses and does not abide in the doctrine of Christ does not have God. He who abides in the doctrine of Christ has both the Father and the Son. If anyone comes to you and does not bring this doctrine, do not receive him into your house nor greet him; for he who greets him shares in his evil deeds.” - 2 John 1:9-11.
Peace?
“Do not think that I came to bring peace on earth. I did not come to bring peace but a sword. For I have come to ‘set a man against his father, a daughter against her mother, and a daughter-in-law against her mother-in-law’; and ‘a man’s enemies will be those of his own household.’ He who loves father or mother more than Me is not worthy of Me. And he who loves son or daughter more than Me is not worthy of Me. And he who does not take his cross and follow after Me is not worthy of Me. He who finds his life will lose it, and he who loses his life for My sake will find it.” - Matthew 10:34-39
The saints have warned us against being in communion with heretics. Over a millenium of saints witness against papism. Will we listen to them?
https://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_decree_19641121_orientalium-ecclesiarum_en.html
The Holy Fathers Forbid Prayer with the Heterodox
Why we can’t pray with the heterodox