I feel like your math is off.

RT = 5/36 = 14% * 22% = 3%

Gyro = 4/11 = 36%

The math of how it really works out does depend on if the two critical slots are free or not and how strict to the rules of determining critical hits one is being.

Going super strict according to the rules of how one is supposed to resolve critical hits(also works if there are no roll again locations):

Since the Center Torso is two sections and the Gyro occupies 3 in the first section that is a 1/4 probability total(1/2 for first section *1/2 for how much of that section the gyro occupies. Since one of four lies in the second section we add a 1/12 probability. So it would be about a 1/3 total probability.

Now yes if there is one or two roll again results you can argue that effectively the probabilities do change and I won't actually put up that much of a fight because the actual final probability does not actually change as it has to land on a gyro location not enigne, something else that can be critically hit, or Roll Again but for the sake of argument it is close enough to fudge and we often do take short cuts in such scenarios.

In the specific case of the Timber Wolf Prime it only has one Roll Again slot in the Center Torso.

So it's close enough probability would be 1/4+1/10 or 35%.

Now the Right Torso of the Timber Wolf Prime and it's ammunition there from the Front/Back by that same consideration though but adds in that the floating critical must also land on the Right Torso. So 5/36*1/4 or a whopping 3.47222...% chance.

I knew Torso math would get interesting but didn't think it would be that interesting.