I bypassed the use of AcceptChanges(), but I encoutered another problem. When a child row is modified when its table is expanded (or has been expanded), the change is not reflected on grid.
InvalidateCells() doesn't help, and accessing the child table model or the corresponding record entry is cumbersome.
Calling AcceptChanges() helps in this case, but again it collapses all rows.
CS2126329214 with child modified_6260fa1a.zip