I got a response today, and I thought it was very enlightening. I'm really pleased that the store takes steps to coach employees about appropriate workplace behavior.
My name is [BW] and I am the assistant store director at [the grocery store]. I am sorry about the experience you had in my deli with J. I will be working with and coaching her about her attitude while at work. I will do my best to be sure that J understands that she needs to give the customer time to state their needs and that she needs to be quiet and attentive enough to be able to hear their requests. J can be very friendly but sometimes being a special needs individual she forgets that tone and volume can work against her. Again I am truly sorry for the way she handled your deli requests and her general disposition on your most recent visit. I will work with her to be sure that this doesn't happen to you again. If you have any other questions or other issues please feel free to call me at [store number], I'd be more than happy to help you in any way I can.
Thanks for your time and input,