When merging PDF documents using iText, the image fields are missing - image

Question

I had a PDF document and needed to add a couple of image fields. I imported the pdf file into Adobe LiveCycle as artwork. I then added my 2 images and saved as a static file. When I view the file using Adobe Reader, I can see the images. But when I try to merge the file with other static and dynamic pdf files created using LiveCycle, the images are missing.
I looked at the following thread
Images (imageField) are not shown after iText PDF Merging
but after checking the solution shown there against my code, I am already using PdfCopy instead of PdfWriter:
ByteArrayOutputStream output = new ByteArrayOutputStream();
PdfReader reader = new PdfReader(baosList.get(0).toByteArray());
Document document = new Document(reader.getPageSizeWithRotation(1));
reader.close();
PdfCopy writer = new PdfCopy(document, output);
document.open();
for (ByteArrayOutputStream baos : baosList)
{
// copy content
reader = new PdfReader(baos.toByteArray());
for (int idx = 1; idx <= reader.getNumberOfPages(); idx++)
writer.addPage(writer.getImportedPage(reader, idx));
reader.close();
baos.close();
}
I have other dynamic PDF files with images that are fine. I wonder if my problem is because I imported the original file as artwork.