Doesn’t that link say the SPD supported the centrist candidate not Hindenburg? Also that the KPD ran their own candidate?

Doesn’t this just show an inability for the KPD to consider working with the SPD because of the fucked up shit they kept doing? My understanding is that fascism was underestimated at the time despite being fought against in the street. Maybe I have to read more perspectives on it, but i thought the KDP didn’t really expect to all be rounded up and killed if Hindenburg got in? The SDP sucked so why would they work together if they didn’t think it was totally necessary, and they both supported different candidates is my understanding at the moment, but idk if that’s correct and will read up more later