Bug#810320:
This should be fixed with https://gitlab.gnome.org/GNOME/pitivi/commit/bb3c1c614298d67351d0297779c765c48feea8a8 since two years ago. Please recheck.
Bug#810320: pitivi: manpage is wrong
Package: pitivi Version: 0.95-1 Manpage mentions interesting options such as --import, but those seem not to exist in this version.