Yes. You can enter IDN domains using the xn-- format.
NameJet does list Pre-Release expired IDN domains like xn--abcd.com from a few of our Partner Registrars. Not all partners offer their expired IDN domains.
You will have to search for the domains using the xn-- format, not the native characters.
We only list Pre-Release domains from our Partner Registrars. We do not attempt to register new names for names dropping during the Pending Delete phase.