I'm still sceptical. I'm not a woman but it sounds reasonable to think that woman have a hard time talking truthfully about how bad they are really treated. It is less likely for a woman to convince the public that something bad was really bad and even from day one of coming out the woman receives more hate than the man.

I also heard that statistics say, there are more false negatives (= woman said bad things happened but investigation says it's untrue) than false positives (=woman successfully lied about things happened).

All that decreases my trust in such a clear "false positive" investigation result, although I admire GitHub for publicly working on that issue. I hope that beside saying that they didn't do much wrong, that they increase whatever they are doing to keep the workplace safe and healthy for the female employees.