No, that isn't correct at all I'm afraid. The Queen doesn't issue decrees. A decision like that would have to go through Parliament and the media would have had a field day. So no, it didn't happen.
Well Lady J, it's an interesting one. The Duchess of Kent converted and the Duke still kept his place in succession because he hadn't married a Catholic, she had converted after their marriage. The Kent's children kept their places in succession until they converted and lost their places. That does beg the question of what would happen, if the Prince of Wales married a protestant but she converted when she was Queen Consort.