Please note I said he was found "not guilty". I did not say he was found innocent.
He was tried for 14 charges. For 13 he provided witnesses who were either there when the alleged incidents happened and who disagreed with the alleged victims' version of events or who provided evidence those incidents did not happen at all.
He was the FM. There are official records when events in Bute House actually took place. He cannot - as alleged - have done something at an event that did not take place. Another alleged victim claimed (in support of her own allegation) to have met a person who was not even in Scotland at the time, because that person's father had died. And so on. For those 13 charges he was found Not Guilty.
The Not Proven charge was for an incident where Salmond went through an official civil service process at the time, accepted full responsibility and apologised. During the trial, that particular incident was presented differently from the way the alleged victim had done at the time of her original official statement. And this was the charge where the jury could not reach a verdict.
I recommend you find the trial transcripts or the very few blogs that reported both the prosecution and the defence case and see for yourself. You might find them illuminating. None of the media reported the defence case; the judge refused his much stronger original defence case and he was found not guilty anyway.
This isn't Scotland's MeToo moment, this is a serious abuse of power in action. If you really hate the SNP, you should look into this trial a bit more closely.