The home group that I am part of is planning a dinner together as our last meeting of the year. Each will bring something, and our families will come along as well.
After we had arranged this, I was asked to travel out of Sydney to give a seminar for my work in Orange. It was an overnighter: a two-day seminar. I would be unable to attend the dinner.
On this news the host thought it would be odd to have a dinner when the 'leader' was absent (they like the unscriptual term 'leader' at my church).
It is the Christian community which is indwelt by the spirit: "where one or two are gathered...". It does not depend for this on the presence or absence of any particular person. Therefore, as group convener, I am irrelevant.