Interesting. When using OPM 2.1 with Kopernicus 1.2.2-1 and Sigma Binary 1.6.1 on KSP 1.2.2, the Plock-Karen barycenter along with Plock's orbit in the binary system is moved from Plock's to Jool's orbit. Plock and Karen stay in their regular orbit, though not as binary system.
Here's a .zip archive containing the Kopernicus logs: https://puu.sh/sHDxJ/11bb0b2c94.zip
Yay, first post!
EDIT: Seems to be an issue with Sigma Binary. Duna-Ike is not a binary system, either, even though the appropriate addition to Sigma Binary was installed.