Readless this is really tough.  A 6x iso makes me think we're looking at a relatively weak player, but maybe that is standard for the game type?  I'm not sure.  But also since the iso is coming from MP, I would tend to think his range is pretty strong, and our TT isn't in great shape.

Obviously the flat pre is perfect.  As far as flop goes…I think there is an argument for just betting out.  Since we're multiway, I don't think we're going to be facing a lot of action from hands that we beat, so betting out gets value from FDs, random floats etc., while making our decisions on later streets easier.

As played, my initial reaction is 'no way fold on flop', but the more I think about it…I don't think it's terrible.  He's betting pretty big into three players, which is generally pretty strong.  On the other hand, he was last to act making his range a little wider.  I think the tournament structure should have an impact on the decision (i.e., if its slower I would lean towards folding and just picking a better spot).  But calling is probably fine.

After you call flop, I think everything else is fine.  I would say leading river would be really bad, since the only thing we beat at that point would be 3 combos of KQs that may/may not be in his range, and possibly 88 (which again, may or may not be in his range).

Overall, just kind of a yucky spot.  As played is fine.  If the structure is good, you can probably comfortably get away on flop and just save your chips.  Not that I would likely fold in game, but theoretically…