inserting info in record along with image

in a previous thread, i learned to use DataAssist insert single record to insert Client File Name from the DFP behavior.

I want to know if i can insert additional information to the db record in order to get the path correct to the image from DFP image upload

ie, the image file from DFP goes to images folder and the file name is filename.jpg.
Using the DataAssist insert single record and Client File Name, it inserts 'filename.jpg'

I want it to insert 'images/filename_lg.jpg'

code is ........$WA_DFP_UploadStatus["WA_UploadResult1"]["clientFileName"].......

i tried .$WA_DFP_UploadStatus["WA_UploadResult1"]["images/clientFileName_lg"]

nothing inserted

thanks for your help,
Jim Balthrop