Islam is a monotheistic religion. We don’t believe in the trinity, we believe that Jesus was a prophet of God, just like the Prophets Adam, Noah, Moses, David, Solomon, etc. We do not worship any deity other than the same God that is shared by all 3 Abrahamic faiths. We also differ from Christians in that we don’t believe in the concept of a divine savior, every individual is accountable for their own deeds. We also do not worship Prophet Jesus or Prophet Mohammed, which seems to be a common misconception a lot of people have. Muslims consider them as mortal, not divine. You are correct in that any gathering centered around honoring Jesus as a deity would be very much against the core monotheistic principles of Islam.