Hmmm, let's just look at it this way...u have one diabetic kitty right?
do u want another one?
I sure didn't so off to wet food for both. Not only did Luna the diabetic improve his overall health, he is now off insulin and within normal BG range... the civvie (non diabetic) improved well with a shiny soft coat and healthy litterbox action.
Most people here who have more than one kitty and at least one diabetic have made the switch over to a wet food diet all around.
One way to introduce a wet food diet to a picky - kitty-krack addict, is to pick up several different brands and flavours from Janet & Binky's (GA) Food Chart.
http://binkyspage.tripod.com/canfood.html
Mixing a bit of one flavour with another works too.
Dont buy a case of one brand/flavour, do some experimenting on a day you have off and can spend some time testing different foods.
You could also, add some wet food bits to the dry, increasing it a bit at a time.
If u go to Dr Lisa's website Feline Nutrition, she covers Transition to wet food very well!
http://binkyspage.tripod.com/canfood.html
But if u have no choice, you will have to feed what ever the cat will eat - that is important!
But it is worth a shot to try one day.