No he was just given a special confidence and appointment by the Pope.
The Pope, in appointing someone, is not endorsing everything that person does or says.
The Roman Catholic LifeSite News frankly disagrees with you. And frankly the above comment is quite naive. The very hallmark of Radcliffe is his open support for homosexuals. If you think these things are done in the Vatican in a vacuum, then once again that would be naive.
Remember, Pope Francis dismissed a traditional pro-life Cardinal from his post:
Pro-life leaders shocked by removal of Cardinal Burke from important Vatican post
Given that I taught theology to several of the Life Site writers, know many of the others very well—shortly after posing my comment I headed off to Mass and saw John Henry Westen, and have at times served as a consultant for them on theological issues, I think I am in a little bit better position to know the mind of Life Site.
The Pope makes tons of appointments. Radcliffe is about one of nearly 70 people appointed to this particular council, and there are loads of councils. Between these sorts of appointments and appointing bishops, the Pope is nominally responsible for thousands of positions—somewhere between six and eight thousand. This appointment is among the bottom tier. If the Pope had appointed him head of CDF, or Papal Theologian (a position traditionally held by a Dominican), I would be a bit more perturbed.
It makes a good story, but as grounds for leaving the Church, it only works if one has a very non-Catholic understanding of infallibility.