My mother and I have tickets for an event, and the seats are assigned. She uses a wheelchair. Will she be ok, will they reassign our seating to accommodate? Should we just bring a different mobility device? I tried writing to them, but no response.

My advice is to call/email them and if again no response, get box office hours and see if you can talk with someone in person.

It would depend on what section your assigned seats are located so I would suggest trying to call them about getting reassigned seats. A different method of mobility may be your best bet if you are unsuccessful in getting a hold of anyone. The main orchestra's floor is easy to push a wheelchair but you will not be able to push the wheelchair down the aisle to get to your seat if in the middle. Have fun!