Did Jesus ever sing a solo? He did sing a hymn with the apostles.
I have a problem changing the worship service where everyone sings equally into one where those onstage account for 50% or more of the singing volume. At that point, it seems to end being worship and changes into a performance. Look at how good I can sing. Not sure that is a worship service.
One instance at least. After the last supper Mark and Matthew state he and the disciples sang a hymn and then went out to the Mount of Olives. Scholars think most likely the Hallel which is Psalms 113 to 118 which are closely associated with Passover.