Excel VBA Code for Dynamic Data Update

I'm seeking an Excel VBA expert to create a code that can update and save random values to closed workbooks linked to a master file via formulas. The updates need to occur as frequently as new data is inputted into the master file.

Ideal Skills:
- Proficiency in Excel and VBA
- Experience with developing codes for data updates
- Familiarity with working with closed workbooks

Please note, the workbooks are linked through formulas, so a deep understanding of Excel's formula capabilities is necessary.