If the dishwasher has adjustable legs, go w/that. If not, the only other way is to 'cut out' (or not install) the new tile where the dishwasher goes. If that latter is the case, you need to 'mark' where your legs will be so you don't tile there. Then, hopefully, you won't see the 'anomily' w/the legs or maybe you can 'make' some sort of apron for the front of the machine to 'mask' the legs.
Your last resort is to get an adjustable dishwasher. My best to ya and hope this helps.