The rules for other versions are mainly derived from tablut and there's no reason to think they're necessarily accurate. The rules Fencer uses are pretty much exactly as they were recorded first hand by Carl von Linne, this is the only "full" recording of rules for a tafl-type game that exist. The problem is that he only spent a few days with the Sami and couldn't speak their language, also he was primarily interested in plants not board games so it's unlikely that he would have tried to ask about the possibility of repeating moves. If repeating moves had been legal there's a possibility that he would have observed and recorded the fact, as he didn't do so is a slight negative evidence that repeating was not legal. I've tried contacting various university departments and Sami journals, cultural organisations, etc in the hope that somebody would be able to clear this question up but I've had no success so far. The main point is that there is no reason why repeating moves should be legal and a draw, it's likely that as this point wasn't originally covered later authors simply transfered the idea from chess. You mention versions with escape to the corners, hostile squares, etc, these restrictions were introduced by players who after some experience felt that the bias was too strong and that white's aim should be made more difficult. I think the bias is an illusion and that the game was of sufficient antiquity that the rules recorded by Linne should constitute a game worth playing for 2000 years. However, the question of repetition isn't covered by those rules and we now have the experience to make a ruling on this question which, from lack of any clarification from Sami sources, might be a good idea. How about a poll of the opinions of members with established tablut ratings?