Rick Warren knowingly accepted an invitation to speak before a Muslim Brotherhood front that was named an unindicted co-conspirator in the largest terrorism financing trial in US history. He is on the wrong side.
I have no problem with a pastor speaking to a muslim organization. I would hope that he would use the opportunity to preach the gospel to them. I have no idea whether Warren preached the gospel or whether he issued "get-along verbage." As a preacher, I would LOVE to be able to address a group of muslims.... provided there are lots of body-guards present.