When I first opened this file, I thought "here's the problem...": The file contains an AFCP trailer which is able to store IPTC information. However, in your case the AFCP trailer only contains thumbnail and preview images, and not IPTC information.

The IPTC in this file is stored in the usual manner (inside the 0x0404 resource of the Photoshop IRB resources of APP13). You say that you are looking for the start tag 0x1c02. This tag actually occurs at an offset of 0x19c5, but in order to properly locate this you need to parse the JPEG segments then the Photoshop IRB resources . Perhaps I can help more if I know more about how you are parsing the file.

- Phil