I wanted to update this. After speaking with Infor we updated our tools to the latest patch versions and updated our porting set to 9.1a (although Infor recommends 9.1c).
After doing this I was able to get bar codes printing in PDFs.
Report Script for this looks like this:
extern domain tcmcs.str50m prod.barcode
prod.barcode = trim$(tisfc001.pdno)
Then directly in the prod.barcode's print expression, not in report script, I used the following:
and obviously set the domain to tc mcs.str50m.
Most importantly, I did not set the "bar code" value to 1 in the report field's layout, I left it as 0. This got my bar code to print to page.
Hopefully this helps someone else!