hah! I wish I could give you a yes/no answer to either question.
Preamps cost from $40 to $40,000 …
The answer to “will it solve the problem”, maybe sometimes. 
Basically, different pedals and different output/input combinations work well or don’t work well. You never know until you try.
Your -10 pad setting should have let the Moog at least attempt to work well with the Carbon Copy. Didn’t know that the Mutli had that output to be honest.
I think you misunderstand what I was saying about the frequency thing. the CC was designed to work within the frequency domain of a guitar. A Rhodes has very similar frequency content to a guitar. A Moog does not … not even close. Analog gear is especially subject to this type of design. You really make it to work with a specific input level and frequency range. Digital is much more forgiving on that front. One of the reasons EchoPlexs were/are so sought after for keyboards is because the builtin pre-amp makes it a chameleon for dealing with both input and output levels (also the pre sounds awesome all by itself if you like that smooth rolloff sound some pres have).
However, the Moog should work well with a BBG delay, so I’m assuming you have level problems more the frequency problems. But, it’s something to consider. Also, using mismatched gear sometimes creates odd effects that you can actually use. It’s a total crap shoot.
I don’t know the delays that are included with your version of Cubase, but what you are trying to achieve with the CC is band reduction and degradation on each repeat. Plus it has modulation, which allows you to create subtle chorusing, or crazy detuned echos. I think you should have one with modulation, but I don’t know if you have one with an analog mode that replicates BBG.