Help with MST with a mix of Cisco and Ubiquiti switches

I have a core stack of 3750's, and 3 additional Ubiqiuti EdgeSwitches connected in a circle topology via 10G trunk ports: https://i.imgur.com/rDZT1D7.png

All with same instance(1), same name("foo" for this example), and same revision(2), but I have 2 root bridges elected, 1 Ubiquiti(1B), and the Cisco 3750x stack(2G).

I've done some packet captures, and compared the MST Config Names, they are both identical.

Any ideas? I'm CCNAish level, so this is stretching me a bit. Does the built in MST0 on Cisco have anything to do with it? No VLANs are using this:

2G#show spanning-tree mst configuration Name [foo] Revision 2 Instances configured 2 Instance Vlans mapped -------- --------------------------------------------------------------------- 0 none 1 1-4094 ------------------------------------------------------------------------------- 

I'm not worried about having multiple MST instances and directing VLAN traffic for now, I just want redundancy.