upstream version 1.8.1 is available. Furthermore, judging from the installed files, the ebuild seems to be broken, i.e. it doesn't install anything meaningful for enabled python targets.
About to do the version bump, but before I do, can you confirm that /usr/lib64/caja/extensions-2.0/libcaja-python.so is not what you are looking for? AFAIK, that is the python module/bindings. On a cursory inspection of the package, and the source here https://github.com/mate-desktop/python-caja/blob/master/src/Makefile.am, that is the only thing created.
Version bumped in bf09d7192838480ea7a801ce5b01a4c9fa135c0a. Based on investigation and discussion with Tamiko, declaring the second part of the bug invalid. Feel free to reopen if something regarding that changes.