Accessing data of a third party data field custom data field

Hi!

Is it possible to access data of a third party custom data field from my custom data field?
It's important to note that the third party data field (SimpleDataField) is not mine, so I can't modify that code. However the data I'm interested in is being written into the fit file by this third party data field. 
Thoughts?

Thank you very much. Regards.