@David_Morris if you have your matches in the PractiScore app on your master tablet, there is also an option to export registrations from the Import/Export screen. You’ll need to do that for each match and then combine and clean exported CSVs in Excel.
Another option is to combine multiple matches in PractiScore app for Android. Tap and hold to select multiple matches on the match list screen and then use Combine option at the top right corner menu. Then you can use same export option on that combined match.