Para 15.6 corra o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/spins:invis:15:unstable:samba/15.6/spins:invis:15:unstable:samba.repo
zypper refresh
zypper install tevent
Para 15.5 corra o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/spins:invis:15:unstable:samba/15.5/spins:invis:15:unstable:samba.repo
zypper refresh
zypper install tevent
Para 15.4 corra o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/spins:invis:15:unstable:samba/15.4/spins:invis:15:unstable:samba.repo
zypper refresh
zypper install tevent