I saw a video that said they were in Canada but the video also said a segment was in Canada but it showed Nanuqsaurus and pachyrhinosaurus perotorum which are both native to Alaska so I'm not sure
I rewatched the episode just to see if this was there (that's what happens when you give me even the smallest excuse to watch Prehistoric Planet). The ceratopsian is there, but I don't think it is a ceratopsian because it doesn't move for the entire scene. For anyone who wants to know, this happens at 6:22. https://www.documentaryarea.com/video/Prehistoric+Planet:+Ice+Worlds/