April and Jerry are Renny's #1 and #2 targets. If she didn't put them up against each other, there would be a risk of neither leaving. There is a three person alliance, and if it were April v. Ollie, and Jerry won POV, you could bet anything that he would take April down. He is very easily swayed by big-boobied-blondes... And, in that scenario, neither of her main targets would be sent out the door.
April and Jerry are two of the least-liked houseguests, and as long as at least one of them stays on the block, then one of them will leave. Ollie could stand a chance of staying against some of the others if Jerry were not nominated, won POV and pulled April down.