Be careful with glueing as DT does not like any at all and you could find it hard to take stain on glued sections. If it must be glued try getting some of your stain mixed in with the glue so that when it dries at least you have trapped a bit of the intended stain colour in the repair. Always test things out on scrap timber first and allow plenty of curing time as funky things can happen as they dry out.