Installing Kwik HUS EZ Anchors at an Angle other than Perpendicualr to the Concrete Surface

We are working with a client that wants to be able to install Kwik HUS EZ Anchors at an angle other than perpendicular to the concrete surface. The intent is to install the anchors up to 15 degrees from the perpendicular to avoid reinforcement in the concrete. They are asking us to provide calculations to justify this installation. Can you provide any help on this?