With Split or Freeze panes you won't be able to get asynchronous scrolling in both directions.
If you have a vertical (left-right) split/freeze, their rows will always synchronise.
If you have a horizontal(above-below) split/freeze, their columns will always synchronise.
If you have 4 panes, the ones diagonally opposite to each other are going to be independent of each other.
To get asynchronous scrolling you can open a new window on the same workbook, arrange them on the screen either manually or by clicking some buttons, make sure they're on asynchronous scrolling:
2022-08-03_213507.png
then we can arrange for the code only to scroll the other window.
To do that a tweak to the code; there are 2 lines:
ActiveWindow.ScrollRow = FirstCell.Row
change them both to:
ThisWorkbook.Windows(ThisWorkbook.Windows.Count).S crollRow = FirstCell.Row
That's been done in the attached as well as changes to cell B1 treated as a red letter.