Reform Yom Kippur Services Question

I went to a reform congregation for afternoon Neilah/Yizkor service the other day. It was a nice and full room and a pretty typical service, until we got to the book of Jonah.

It seemed unusual to me when the Rabbi introduced a guest – a Christian clergy member who gave a sermon on the story of Jonah and then led a portion of the service reading the haftorah (in english).

This wasn’t promoted as an interfaith service, and I’m not sure I would have expected this would be done at a URJ affiliated temple on Yom Kippur. That said, the crowd seemed unphased, so maybe I’m out of touch.

I’m curious on similar experiences others may have had at high holiday services, or how you think you’d react to this as an un-announced bit of programming.