I am not sure why your column names are showing up with superscripts. On my side, I had no issues importing the attached csv file using the normal method of File -> Open with Preview.
By the way, if you are using JSL scripting already, you may be interested in referencing columns by number instead of name. Here's an example from the Scripting Index entry for the Column function:
Names Default To Here( 1 );
Open( "$SAMPLE_DATA/Big Class.jmp" );
col4 = Column( 4 );
ht = Column( "height" );
col4[1] + ht[2];
Notice that you can reference a column as "Column( 4 )" or "Column( "height" ); both are ok. This gets rid of any reliance on exactly matching the column names. This is a good fix if your data table is always formatted the same way (same number and order of columns).