When Benzema was still playing for Real Madrid, Real Madrid always use 4-3-3 strategy, so all of them should able to play in their own positions.
Actually this strategy can still be done with Mbappe, Vini and Rodrygo up front regardless of who will be the actual center striker Mbappe, Vini and Rodrygo can also still depend on how the needs are.
In several matches this season we have seen Vini or Rodrygo placed at center striker when 4-3-3 and indeed the results although need further adjustment but I think it is still good enough so something like this can still happen.
But if in the end Ancelotti still wants 2 strikers supported by 4 midfielders who do function as defensive midfielders, 2 playmakers and 1 second striker it means that Rodrygo is likely to share or his position will be slightly changed by Ancelotti because we know with Ancelotti's tactics any player he can place in a position that does not even match his style and this season we can see that Camavinga and Tchouameni and even Jude who are new players are placed in positions that are not ideal positions but they still play very well.
I think that Madrid will play the final in a very safe way, that is to say, they will focus on attacking, they will not let Dortmund breathe and as soon as they get 1, 2 or 3 goals I imagine that they will close up in defence, as they did against Man City and that is something that is allowed. Personally, I have always said one thing, if we start to see how many strategies can be carried out for a final, it is useless, you have to have 2 strategies at most and one is for when you are winning and the other if you are losing. I am not going to say that Madrid is going to win by a landslide, because you only have to look at the example of Leverkusen against Atalanta.