When creating a feature class in a FGDB export there are rules that need to be followed with the naming convention. Most of the rules is already handled by Fulcrum. However, the one rule that is not is the rule that the name must start with a letter. So if your app's name starts with a number it will result in the export failing.
To get around this, you can change the name of your app so that it does not start with a number. For example, changing an app's name from "2018 - Field Data Collection" to "Field Data Collection - 2018" would satisfy the rule and result in the export successfully completing.