EZ Dome is not a good option with HDR files. The dome is a mesh light that projects the basic image. HDRI contain luminosity information that mesh lights do not read. Unbiased rendering engines like Octane, Iray, LuxRender, and Cycles use an "Environment" setup to properly project HDRI files. Superfly uses the Background node for the Environment.

The following images used HDRI Haven's Sunny Vondelpark HDRI

Dome

Background

The Background is able to project the HDRI's sunlight and the Dome is not able to fully project the light. Dome objects like EZ Dome work in Firefly because there is no "Environment" built-in the rendering engine.