I’d be a dissenting voice. I don’t believe The Zodiac Killer had anything to do with Cheri’s murder, and further, I think that RPD have had every right to resist the idea that her murder be included "in the series".
Now – whether their investigation has been handled correctly in respect to other suspects, well I couldn’t say, but since they’re a professional outfit who had a VERY high profile case on their hands (even before the letters were written) to which they gave a lot of resource – and since they’ve been working the case for a long time, I expect they’ve pretty much done everything they could possibly do, one way or another, including spending on some pretty elaborate DNA testing.
My 10 cents.

I agree with smithy for the most part.

Not that there haven’t been some lousy cops handling things at times, surely there have been determined investigators over the years. I am actually surprised the RPD has told anyone anything at all. Or any PD for that matter.

I’ve encountered several posters who complain bitterly of Riverside Police Department’s handling (or, mishandling) of the Bates case. I’m no attorney, but how’s this for an idea: That members of zodiackillersite, either collectively or singly, petition the California Attorney General for an investigation of RPD’s ineptitude. Kick it around, and see what you come up with. Nothing ventured, nothing gained….

IMO, The Z. was really only responsible for LHR, BRS, LB, and SF and those cases should be focused on before The Z.’s already dubious word, having bluffed "us" at least three times already, is taken for previous murders.

Just my theory on LHR, BRS, LB, and SF but I could be wrong
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