As seen in Deathly Hallows, Dolores Umbridge actively supports the Ministry anti-Muggle doctrine endorsed by Voldemort. So, she was not an 'innocent bystander' by any means.
Is there any canon information if she was punished for that? Or did she get away as usual?
Yes. Her Pottermore page surmises as much.
With the fall of Lord Voldemort, Dolores Umbridge was put on trial for her enthusiastic co-operation with his regime, and convicted of the torture, imprisonment and deaths of several people (some of the innocent Muggle-borns she sentenced to Azkaban did not survive their ordeal).