48 hrs isn't enough. Plus the OP gave Superman prep as well.
I do think Doom would do more than Prep than Superman. As he is smarter and much better at planning. If they existed in the same universe then Doom would have a better shot as Supes would've faced people Doom is familar with or maybe even Doom himself at some point. So he would be able to devise something to counter Supes.
Without that, the power gap plus giving Clark prep is a bit much.