User blog comment:WoodlandGirl/Questions (SPOILERS)/@comment-5659316-20121226052007/@comment-5659316-20121227000953

It was probably not Laura (though it was FREYA, as in the character, just not the same actress), and even if it was, she probably wouldn't get credit for one arm sticking out. My guess is that they couldn't get her back for the finale so they just showed her arm, or if they could/did, they cut her scenes for time (highly unlikely, but not impossible). And if they cut all her face time, then they would not give her credit. An arm/hand does not get any more credit than the stock-footage they have of a leaf with a drop of water in it that they've used for several episodes. If she did (big IF, mind you) have scenes and they cut them, Laura's name wouldn't be mentioned. It's possible that the arm in The coming of Arthur wasn't Laura, either. The bit with her face in the puddle was her, as she was credited for, but the arm could have been anyone really. Now if she had had a voice over moment (like John Hurt gets, sometimes even when Kilgharrah does not appear) THEN she would have been in the credits.

Also to those of you who doubt it was Freya's arm, look at WHO wrote the episode. Julian Jones. Freya (and her arm!) have appeared ONLY in episodes he's written... He wouldn't just put a random Arthur arm cameo when he could use one of his own personal characters and conclude their story, however breifly.