The 90s cartoon which is quite good, issues mentioned elsewhere aside, renewed a lot of interest in Tintin.
So I think Tintin in the Congo was released in English more for collectors, it's still often absent from collected editions or the back cover of single books.
These guys suck and are being hypocrites to save money.
Interestingly the catholic stance on abortion is relatively new from the 19th century. Prior to that abortion was considered the better alternative to infanticide.