/usr/lib/x86_64-linux-gnu/libosgQt.so is in libopenscenegraph-3.4-dev 3.4.1+dfsg1-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libosgQt.so.131
/usr/lib/x86_64-linux-gnu/libosgQt.so.131