Glad Bobbo mentioned the wet/dry with the Chorus cause I thought that might be the case.

On the 4CM, two amps thing .... well you will be living in exciting times !

You can either keep it simple or go more complex depending on what you want.  I am assuming that each amp is a full amp (not just a power amp) and each has its own cab(s).

Simple is using the pre-amp from just one of the amps but the power amps from both.   To do this, setup the full 4CM on one of the amps but then just add a single additional cable running from the 1/4" RIght output on the POD to the FX Return on the amp (a second 'Cable 4').   Now, you can either run both amps together (Mixer Channel A centre) or Amp A or B only (Mixer channel A Left or Right).  This can be set on a preset by preset basis.

Complex would be using both pre-amps and both power amps on both amps.  You would need a special 1 x TRS to 2 x TS Jack cable (a Stereo Y cable) and a long one at that.   This becomes Cable 2 in the 4CM hookup.  You would also two additional cables as follows:

The cable hookup would then go (deep breath) ...

• Cable 1:  Guitar -->  Pod Input (as usual)
• Cable 2:  Pod FX Send --> 
  • Amp A Input
  • Amp B Input
• Cable 3a:   Amp A FX Send -->  Pod FX Return (Left)
• Cable 3b:   Amp B FX Send -->  Pod FX Return (Right)
• Cable 4a:   Pod 1/4 Out (Left) -->  Amp A FX Return
• Cable 4b:   Pod 1/4 Out (RIght) -->  Amp B FX Return

Setup all the levels as per the 4CM doc of mine that I think you are using.

From this point you would be well advised to check out the routing within the POD with a copy of Bobbo's HIgh Gain tone guide in one hand and a bottle of paracetamol in the other.  In principle you should be able to get one or both amps working at the same time with either pre-amp into either power amp, by using the mixer. 

I have to say that all this is is really jacking up the complexity on a cabling setup that is already quite a challenge to get comfortable with.   Sounds like fun!  Let us know if you go this way and how it works out.