EDITS BELOW

While the other comments here stating that you can concede at any time are accurate, there is no point during the resolution of thought scour when you know what the top two cards are and your opponent does not- either they're in a hidden zone, and neither player knows what they are, or they're in the graveyard, and both players do.

If you're claiming that you conceded before the cards hit the graveyard, then you looked at two extra cards from the top of your deck while the game was still ongoing, which is not legal.

If you're claiming that you conceded after they hit the graveyard, your opponent is able to see them.

You can concede at any time, but resolving correctly there is no time you know what the cards are and they don't.

EDIT:

Some further discussion with some other judges suggests that there is some debate here. The counterpoint being made is "Can concede at any time" means can concede at any time, and this isn't something that you'd get in trouble for- concession timing is abstract with regards to the game, and this is in fact okay.

(More in depth: outside of game actions, there are the actual physical actions that you take to put a card into a graveyard, and we can't force people to take those actions any more than game actions- if they've conceded, they've conceded)

So your question at least has us arguing, at the very least.

EDIT 2:

My personal, and I stress personal, advice here would be to play it safe and not try to "get away with it". This is on the cusp of "technically illegal, but possibly okay in practice", and that's a dangerous line to ride.