Two things:
1. It’s been said that that picture shows him showing thanks and respect for a gift. This you obviously disagree with (and I do too by the way.)
2. It’s never been actually proven, to my knowledge, that that book is indeed a copy of the Koran. I have also heard it said that it was a copy of the Bible given to him by a Coptic cleric. The only “proof” that it’s a Koran is blog post after blog post after blog posts merely claiming it was the Koran. I’ve never seen an article from an accredited news source that independently verifies it was the Koran. I’ve looked. If you can find such a source feel free to share it.
So until and unless it’s shown differently I’ll believe #2. Even then I’ll have the right to disagree as in #1. Don’t fall into the Protestant/non Catholic trap that demands perfection from Saints (while on Earth). No one has ever said a Saint now in Heaven didn’t make a mistake while on Earth. After all a Saint isn’t someone who never sinned. Probably someone who sinned 100 times, but confessed his sin 101 times.
This isn't just a "mistake". This is another example of his MANY actions wrt VII's false ecumenism. He taught the Church through his actions that these actions were Catholic in nature. I wonder how many Catholics he has taught that it's ok to kiss the book of a false religion.
Yet, saints are CLAIMED to actually BE in Heaven with no proof.
Strange world; ain't it!