I think the title is supposed to say "Trump says peace deal tomorrow" and not "Iran".
And yes we will see who and who does not have any cards in this negotiation, based on whether Trump is dictating tomorrow or Iran is dictating 'not tomorrow'.
And by the way, it is not even a 'Peace deal' being negotiated right now despite the Trump spin. It is an MOU that would set the stage for "Peace Deal" negotiations.
What the MOU does is have both party agree, in advance the outline of the talks, so it is not a complete waste of time with people talking past one another. So one party does not show up saying "i will negotiate on the subway but not the airport" and the other shows up saying "i will negotiate on the airport but not the subway", and thus the trip was wasted. An MOU is established and agreed to that 'both the airport and subway will be discussed' and once agreed you set up the actual negotiations to follow.