How much does your dog weigh?
How many minutes ago did she ingest it?
You can give her 1 and 1/2 tablespoon of hydrogen peroxide by mouth and she will vomit in about 15 minutes. If she doesn't, you can give her an additional tablespoon after 20 minutes. Just catch the vomit and identify the dryer sheet.
Worst case scenario, if it doesn't come up, she should be able to pass it through with her size - but it would be better just to get it up and not have to worry about it.