Issue with compiled excel Add in - database toolbox query is not successful - fetch error

I am having a problem with a Matlab compiled Excel add-in. The function runs fine in the MATLAB environment (data is returned from the database) but I get the following error when running the function through the excel Add-in - See attached .png -

The function takes two input argument, start and end date. Originally I had these in date format, but I changed these to number and convert with datestr in the function instead. This didn’t solve the issue.

Is there anything I need to do to ensure the database toolbox works within a compiled Excel Add-in? Could you point me towards any relevant documentation please?