How To Query The ValueFunction Of A Different Trained Brain While Training An Agent

Here is my problem. I have two brains:

• A trained walk-brain that handles a running/walking/standing humanoid character
• An untrained jump-brain that handles launch/airborne/land states of a jump.

The jump-brain should learn to land in a pose that will lead to a successful/smooth transition to standing/walking/running. What I would like to do is query the value function of the walk-brain at the moment the character lands. If the value function of the walk-brain is high (good expected future reward), then the jump-brain gets a good reward. If the value function of the walk-brain is low, then the jump-brain gets small-negative reward (the walk-brain will probably fall over after landing).

I need to be able to query the walk-brain (inference mode). While the jump-brain is being trained (learning mode). Both brains are on the same agent.

Is there a way to rig a setup like this in an ML-Agents training scene?