This is correct. They're mismatched totally. I'm just trying to rig something up with what I already own rather than buying something new
I think it's gonna be tough.
Considering the cabs are so mismatched, I would assume they also want some separate eq control on them.
Even in a 2 quilter situation (or quilter feeding a power amp), you only have one set of tone control from the original Quilter. This could be problematic if you don't also have matching cabs that like the same EQ settings.
I'm assuming you are using the Quilter rig to cover FOH and the WW rig as your monitor.
What about this? It involves buying something, but it's pretty cheep (cheaper than a new amp or cab to be sure).
Here is a XLR attenuator that will knock your signal down by 30db, and it's $20.
Whirlwind IMP Pad - 30 dB
Bass -> Quilter (rig 1- eq and vol as needed for FOH) and then hook the XLR pad to the line out of your Quilter. Then use a XLR (f) to 1/4" TRS cable, and run that from the pad device to the front end of your other amp.
This would give you two separate rigs. Of course the signal out of the quilter would have the eq settings from your quilter, but you might could make those up as needed with the eq on your WW set up.
Here is an example of one of the cables. 20ft, so you could have the amps as far apart as you needed. The cable is grounded, so I don't think it would cause problems with buzz. Get the cable in what ever length you think you need to have the amps where you wnat based on your stage set up.
https://www.amazon.com/Female-CableCreation-20Feet-Microphone-Speakers/dp/B01JY2A7JI/ref=sr_1_29_sspa?ie=UTF8&qid=1548946725&sr=8-29-spons&keywords=xlr+adapter+to+1/4&th=1
All this would cost you less than $50, and give you a 1/4" line out of your Quilter with a signal that you could get down low enough that it shouldn't be a problem running into the front end of another amp. I would think even with the Quilter cranked, a 30db pad would be good.
Shure makes one of those XLR pads that has a switch on it for 15, 20, or 25db pad, but it's a little more $. The Whirlwind also comes in all levels up to 40db. You also might have a active / passive switch on your WW that can knock it down further.
No affiliation with any of these products, just examples of stuff you could try. I would also let the group chime in and let the hive mind work out any potential problems with this solution. Also maybe chime in as to what level pad you might want.
Sorry for the long post, and hope it all makes sense. Just woke up an the brain is still a little fuzzy.