Your installation would not pass code under the UPC, due to lack of air gap...but it may be legal where you are. But that aside, there is a problem....the dip between your high-loop and the wye fitting. Water will sit there, and potenially DIRTY water from the sink drain may settle in there. There will always be residual water in the bottom of the DW...where can it go? But hopefully, after the last rinse, that water will be clean. You can freshen the DW by putting a cup or two of plain white vinegar in and running a rinse cycle.
That accordian coupling you have will be seriously gunky inside, and that in itself can be a odor problem.