Got it [here](amazon.com/dp/B01D47DUD4/ref=cm_sw_r_cp_api_glt_fabc_WKP4TDCS8R8FS97Z4VYF?_encoding=UTF8&psc=1) it even has the same USB ID as the one listed on the dolphin wiki, the one ending in 0A03. I ordered an official refurbished rockband one off amazon, going to try that one next. I even tried the first one on a different computer, and on several different dolphin versions, including the first version where USB passthrough was enabled, and using the old USB passthrough method, rather than libusbk, all gave the exact same error.
I find that if you do not have much background noise and you are looking for something cheap, get one of those Rock Band microphones. The one I have is this one, and it works great: https://www.amazon.com/TPFOON-13FT-Wired-Microphone-Guitar/dp/B01D47DUD4/ref=sr_1_2?keywords=rock+band+3+microphone&qid=1582685585&s=videogames&sr=1-2