Currently there does not seem to be any method to test if a table is locked if it has been locked either through the red triangle drop down or the Lock Data Table() function.
When a data table is locked either through the drop down or in JSL with dt<<Lock Data Table(1); testing to see if the table is locked using dt<< Get Edit Lock(); returns Empty(), which doesn't make sense. My expectation is that it should return a list: {"Modify Cells", "Add Rows", "Delete Rows", "Add Columns", "Delete Columns"}.