If it's any help, I saw Doncaster only last week in the Challenge Cup at Warrington, they got beat 68-0 but I don't know how they managed to get nilled, they didn't really deserve that scoreline.
They had three good chances all match, and were only stopped with two of them by being pushed into touch a split second before the try, and also by kicking the grubber a little too far and the ball going dead. I would say their biggest threat is down the left wing, David Scott and Shaun Leaf know how to get forward but they are not particularly quick, if you are expecting a run from them, they are easily brought down.
Other things I noticed, they put in a lot of tackles and have some really big lads in the middle of the park, the scoreline would have been even higher if it wasn't for this consistent tackling from Doncaster.
Warrington's tries were quite evenly spread out, but there was perhaps a few more going in down the right wing and right under the sticks, I would say their left wing (your right wing) is their weakest point, attack that with some quick wing-play and you should get a few tries alright. Against quick wingers (in this case Kevin Penny and Joel Monaghan) Doncaster can seem to be a little slow off the mark, Kevin Penny scored an Eighty metre wonder try (one of the best I have ever seen) straight from the 20 metre restart, Doncaster did seem a little slow to get back, but even their back two were easily ran through.
Just a few ideas, I reckon this is a match for speed, because they are not particularly quick, and perhaps their left wing (your right wing) is the place to attack, good luck Whitehaven!
