Yeah, You can totally use the midi clock of the KP3 for the minibrute! I use a kaossilator as the master for my set up.
You'll need to set your kp3's midi to internal:
1) Have your midi cord going from the KP3's OUT to the Minibrutes IN.
2) On the kp3, hold shift and press 4 [midi filter].
3) You'll have 5 options. Clock, program, Control Chg, Note, and System. Select Clock
4) You'll have 3 options. Internal, External, and Auto. Select Internal.
optional 5) If all you want is the BPM to match, I recommend disabling the program, CC, note and system midi options. That's what I do anyways. I honestly am not too familiar with Midi yet.
Done! Should have the KP3 set as your master clock and the minibrute should follow along. Test this by messing with the bpm on the KP3,
Hope this works for you!