This is all very strange. The Parliamentary reply to Baroness McDonagh does not list New Hall prison, which is where Karen White was held, according to several newspaper reports.
This article from Nov 2018 says "The lag, born David Thompson, sexually assaulted two female prison guards during his sentence for raping two women".
An earlier article from September said "A transgender lag carried out four sex attacks at a women’s prison while on remand for rape" and goes on to say that White "admits two sex attacks at the jail between September and November 2017. A judge ordered the remaining two to lie on file."
So it looks like White was convicted of two sexual assaults at New Hall and two others (on prison guards?) were not prosecuted.
Yet none of this info showed up in the answer from Parliament. Are both the newspaper articles and Rory Stewart mistaken?