I am trying to merge 2 simple PDFs, both one page in length, together as one page.
Page 1 / 1
You can define the PDF page number in the output, so give the first PDF page 1 and the second page 2 and output to PDF.
Have a look at this link https://community.safe.com/s/question/0D54Q000080hEMvSAM/write-multiple-pages-to-one-pdffile-using-only-one-pdfpageformatter