Cooperative Polygraphy - S5-E4
Trivia: Pierce's boat that he gives Troy to sail the world in is called the "Childish Tycoon." Donald Glover, who plays Troy, uses the stage name "Childish Gambino" in his music career.
Cooperative Polygraphy - S5-E4
Trivia: This episode features a storyline involving the "Ass Crack Bandit", a student (or teacher) who is notorious on campus for dropping coins down the pants of students and faculty members. This entire storyline is a callback to the Season 2 episode "Intro to Political Science", in which the character Annie makes a brief passing reference to the "Ass Crack Bandit" during a speech.
Answer: The implication is that Jeff will still be teaching at Greendale after Annie and Abed leave. As for who became vice dean? It's never shown, since it's not really important to the series.
TedStixon