Thank you again!
General Note to those with a similar problem: It looks like @robrs and @pennam were right on the money - there was a weird error between my thingProperties.h and main tabs, which ultimately ended up being a variable shadowing. There is also another forum post as well that troubleshoots a similar issue.
Thank you to all who helped me troubleshoot my issue, and best of luck to anyone with a similar issue to mine!