SL3 Drag and Drop - need to send incorrect items back to start point after user submit's first attempt

Hi

I have a drag and drop where the user needs to place numbered boxes (1 through 5) next to the appropriate sentences.

After user hits SUBMIT, I need any wrong answers to slide back to the original starting location... so they know those are incorrect. (Or, I'll settle for ALL the number boxes returning to start position after submit if 100% is not correct, but I prefer the former.)

I can not find a simple solution via the SL3 interface to do this. I'd assume this functionality would be built in. I do see the option to send the boxes to original start point when dropped on an incorrect answer. But we need them to hit SUBMIT first, so it's counted as an "attempt."

Suggestions welcome and appreciated. Thanks.

Karen