Can I cook with smoked shrimp shells?
Sure, shells have a lot of flavor and make excellent stock. You could also put them right into the tomato sauce, but then you'd have the issue of getting them back out of the tomato sauce without taking most of the sauce with them.... I would therefore just simmer them in water for a while until I got a concentrated stock, and then put this into your sauce.
agreed - theoretically it should be fine and actually sounds quite tasty.
I say theoretically because I've never tried it. The smoking process could dry out the shells to a point where they loose most of their "shrimpy-ness" and you might end up with just the taste of smoke and whatever seasoning (if any) they used.
But it is definitely worth a go. You could use them in a tomato sauce I would think but as visciole pointed out you would need to strain them out. So I might simmer them in tomato juice or sauce - strain - and then saute any onions/garlic etc and add the infused tomato sauce and whatever else at that point.
Did you do it?