Yeah that arpeggio is meant to imply a V+ (G+) which is why it uses E♭ instead of D. V+ is just serving as a substitution to V. A less common dominant chord than V so it might not be for everyone
So implying a G-B-E♭ chord (G is being played in the duduk melody). The A is there for melodic minor flavor lol
Up till that point in the progression I was mostly using 1-5-9 voicings so maybe the break from that pattern was jarring.
Thanks for the feedback!