Well, let's look at this purely mathematically then.
I'll assign Villain's range to be:
AK,AQ,44+, any diamond suited connector from 76 up, plus KJd.
We shove. For this exercise lets just assume the third player folds 100% to our shove. Let's also assume that Villain will fold 77-JJ, AQ, AK and call with 44-66, QQ-AA, and the flush draws.
So we need to figure out how many hands he is folding vs. how many hands he is calling with.
77 88 99 TT JJ - six ways to make each one, or 30 hands.
AQ - since we have the diamonds, there are 6 other AQ hands.
AK - since we have the Ad, there are 13 ways to make this hand.
QQ(3) KK(6) AA(3) 44(6) 55(6) 66(6) 30 hands.
KJd 76d 87d 98d T9d JTd KJd - 7 hands.
Villain folds 49 hands out of 86, or 57% of the time.
Villain calls with 37 hands out of 86, or 43% of the time. When he calls, our equity against his calling range is 42%.
57% of the time we win the $38 pot to a fold.
43%(58%) or 25% of the time we lose $61.20 and double up Villain.
43%(42%) or 18% of the time we win $61.20 plus $7.50 in dead money, or $68.70.
Expectation = .57($38) + .18($68.70) - .25($61.20) = $18.73
I also did the exercise with Villian calling with all his pairs and with AK in addition to the calling hands used above, and our total expectation came out about the same.
We'd have to narrow Villian's range a bit to come up with negative expectation. This isn't really the outcome I expected. Looks like shoving works here, if I didn't make a mistake.