復職 and 就任: returning to work and taking a position
Compare return after recovery with taking a chair or theater company role, preserving the difference between a wish, a meeting, a celebration, and a future plan.
復職: return timing and a meeting with an employee
復職 (ふくしょく) means return to work or reinstatement. 「長い療養を終えて来月から復職する。」 means “I will return to work next month after a long recovery.” The speaker will return to work next month after a long recovery. 来月から gives the starting time for the return, so the sentence should not become a claim that the speaker is already back at work.
「会社は復職を希望する社員と面談した。」 means “The company met with an employee who wished to be reinstated.” The company met with an employee who wished to be reinstated. A wish and a meeting are stated; approval of reinstatement and an actual return are not.
就任: an appointment celebrated and a future role
就任 (しゅうにん) means take office or appointment. 「新しい委員長の就任を皆で拍手して祝いました。」 means “Everyone applauded the new chair's appointment.” Everyone applauded the new chair's appointment. The role is chair, and the celebration is described as an event that occurred. Do not identify this chair with the employee in the separate reinstatement meeting.
「彼女は来月、劇団の代表に就任する予定です。」 means “She will become head of the theater company next month.” She is scheduled to become head of the theater company next month. The Japanese 予定です explicitly states a plan, rather than an office already taken or a celebration already held.
Keep wishes and plans distinct from completion
With 復職, look at the relation to work that someone is returning to. With 就任, look at the position being taken. Preserve the recovery, meeting, role, and date only where each example supplies them.
A wish to return, a meeting conducted by the company, a return beginning next month, and an appointment planned for next month are distinct kinds of information. Expressing an intention or a plan is different from reporting its completion.
Do a meeting with an employee wishing for 復職 and a plan for 就任 as theater company head 来月 describe completed appointments?
Show the answer and why
No. The first reports a meeting with someone who wants reinstatement, without confirming its approval. The second gives a planned role next month. The return after recovery and the celebration of the new chair's appointment are separate examples with their own timing.