I think there is also the whole idea of state visit, the head of state comes over as our guest.... it is actually unusual that the catholic church is contributing to the cost of the visit normally only personal body guards, private cooks etc are paid for by the visitor, It is because he is undertaking activities as head of a church as well as a head of a very small state. in return the same applies when the Queen travels abroad she is the guest of the host nation.
No one can condone the terrible things that have happened within the catholic church and also in the church of England it happened in my parish when I was a child and the curate concerned was sent on a long 'retreat' then no one heard any more about him. At least it is being spoken of now so can start being dealt with and help offered to the victims. I think the Catholic church is ahead of the C of E in this now. Hopefully it will be considered further when the head of state for Vatican City meets with vaious officials etc over here.
We may not approve of this particular guest... but then Robert Mugabe, the Chinese leader etc came here too and I don't approve of them either