First, dichoric is not glass, it is a metal and so resists fusing to glass. The cap will have nothing to stick to in the fusing process unless you remove some of the dichoric, especially at the edges. The glass will behave like two separate pieces of 3mm glass and try to draw up to a thicker piece.
Second, the glue burns off much earlier than the glass begins to stick. the glue will burn off at about 200-300 C. The glass does not begin to stick until about 600-670C.
So you need to make sure your stack or lay up of glass is stable before you begin to fire it. This can be done by adding pieces of clear to support cantilevered pieces, for example.