There's no difference whatsoever in how PHNL and KFLL are made.
The apron texture is in the AFCAD file so, the only possible explanation is either you have another AFCAD in conflict or, by editing the PHNL AFCAD, the apron polygon was somewhat lost and, you might have created a duplicate AFCAD yourself, because ADE always creates a BGL with a new name when saving back, unless you specifically tell it to use the existing name.