Yes, it's fine to not know every word in one's main language, even as a journalist,
if you're gonna take a stand on the existence of a word in a format where you have every opportunity to check first, you should be right,
but as a journalist you should above all know to issue a retraction or correction if you have published something that was incorrect.
If you 1.5 weeks after being corrected by a dictionary on something so prestige-less still haven't said something as simple as "I was wrong", you are wrong for the job.
That's my opinion.
Still funny though.