Won't work. You have no input modules that can step the signal level up to synth levels, so there's literally no way to input anything from the Drumbrute. And as a result, there's also no envelope followers, meaning that you won't be able to trigger that Befaco ADSR from your audio peaks (which you'll need to do to process percussives well).
farkas makes a very good point: go to a larger cab. I have no idea why people seem to think they need to jam ALL of their functionality into a tiny one-row case...except...STOP WATCHING YOUTUBE, DAMMIT!!!!! Just because someone on there with extensive experience can do a build in 104 x 1U does NOT mean that everyone could or SHOULD do this! In fact, save for very specific-mission builds, I never advocate using small, single-row cabs.
There's also a matter of cost. This runs about $2500 for the modules alone. farkas mentions stompboxes as a potential solution, and it's something you might want to entertain for simple processing tasks such as this. You could spend that same amount on some VERY screwy, trippy pedals and wind up with processing for the Drumbrute that makes it sound like nothing else on the planet. Or better, spending HALF of that, and still arriving at the same result. Or even BETTER, getting on eBay or Reverb and getting some super-cheap rack processing gear, which goes for dimes on the dollar these days since everyone's gone over to plug-ins. F'rinstance, back when the Lexicon LXP-15 came out, it went for about $1400...but now, minty ones go for about a TENTH of that used.
Modular isn't always the right option...and where solely processing is concerned, using proper effects processors (and combining new devices with older ones) is the correct way to go. Modular isn't a panacea, and this is one case that shows that.