I's a fine point. We say "meet" and "meet with" to mean gather or confer, and it's used even if everyone already knows each other.
- My union will meet (gather) tonight.
- I will meet (confer) with my lawyer tomorrow.
Since he was new, both "meet" (encounter for the first time) and "meet with" (join together/confer) make sense, although the meanings are different.
Student or Learner