spiceinit is not applicable to HiRISE RDRs. spiceinit is used to attach spacecraft pointing/timing information and a camera model to an EDR so that each pixel can be located in a geographic space. The RDRs are map-projected products derived from the EDRs (which is a more “raw” product). The RDRs contain image data that have not only been transformed by applying the camera model, they have been projected into a geographic coordinate system and orthorectified onto a global 3D shape model for Mars.
If you want to follow the autoseed workflow, you will need to start with EDRs, not RDRs.
I see that Andrew Annex had an interesting suggestion about using his wrapper for ASP’s ipfind/ipmatch in your other thread. I think you could use the RDRs as input to that process.
Good luck.