You need to also look at the rates for the overall population - by crime, age, mental health, etc to get a picture.
Agree.
It is entirely unrealistic to expect a zero suicide/murder rate for transpeople in prison. Because sucides and murders happen in prison. So some are to be expected.
Until the numbers are crunched for both trans and non trans sucides (and murders if any body knows of any) it cannot be known if transpeople are at a particularly elevated risk in prison compared to the rest of the prison population.
And even then more analysis would be needed to establish that the sucide/murder was caused by being trans in prison, rather than transpeople in prison possibly tending to have a higher than average number of severe MH issues that left them individually at a very elevated risk of inmate conflict or sucidal impulses.