just reading by the face of the details presented...
rider A lost control of the bike with a contributing factor of road debris.
rider B was unable to avoid the resulting collision.
officer not returning a call?
contact the supervisor of the officer. usually by calling the department.
if no result there, run it up the chain till you get results.
officers will often contact the entity responsible for road maintenance in the area where some hazardous debris is. ultimately, its the responsibility of that entity to remove any hazardous debris. that could be state, county, city or even a contracted agency. only way to know would be to contact someone in the public service department, inquire if they are in fact responsible for the area in question... and make them aware, or ask if its been resolved.
granted this occurred in 2008 and this is just for speculation.