Frozen column cells cannot enter editing mode when pressing numeric and alphabetical keys

The getCellContent function has correctly set the returned cell object. When the table is set to freezeColumns={3}, the cells in the first three frozen columns cannot be edited in keyboard input mode

Reproduce the issue with a grid using getCellContent and freezeColumns={3}, then trace the keyboard-input editing path for cells in the frozen columns. Done means numeric and alphabetical key presses enter editing mode consistently in both frozen and unfrozen cells.

Written by the indexing model from the issue text.