It seems very strange that a new joiner on a specific type gets his/her very first feel of the airplane on (very) short final. A short final this person isn't familiar with at that.
Give people some stick time climbing out, then gradually build out the exposure, including some proper time hand flying the long approach. On the candidate's first landing, the TC should be sharp as a razor to take control at the first sign of trouble. Especially on the 300, which is a bit less forgiving on pitch deviations
What should have been a nice and memorable training experience for the FO, now potentially has significantly dented their confidence. And I can't help but feeling for the captain. What an inglorious way to end a career. I understand this was his last landing as he was close to retirement.