ASRS 2065284

While on approach in to SDF we were brought in on a downwind for Runway 35L. We were still at 250 kt. and asked if the Approach Controller still wanted us at 250. He said to expect slower in base. The controller eventually gave us a vector of 080. We read it back but then realized that that vector was right at inbound traffic so we confirmed the heading with the controller again. He repeated it and told us to turn right away. We complied. He then re-vectored us to 010 to join the localizer. We continued inbound for some time. The controller still never slowed us so at a 15-mile final we told him we were unable 250 kt. We had decided we could no longer keep 250 kt. at a 15-mile final and safely meet out stabilized approach criteria. The controller angrily replied turn left to a heading, breaking us off the approach, which also turned us directly into wake turbulence from the heavy jet in front of us. While we were encountering wake turbulence the controller came on the radio and told us we had a possible pilot deviation and to copy a phone number. We complied. We then got resequenced around for the approach and at 15-mile final we had been given 170 kt. until final approach fix, 80 kt. slower then the previous approach. We landed normally and taxied to the gate. We called the Supervisor once we were at the hotel. The Supervisor was very apologetic and informed us there was no evidence of a pilot deviation.