There are a few different RIPs that can be used with Indigo presses. The one normally used by HP with the Indigo uses the Harlequin RIP technology from Global Graphics. Other RIPs available from third parties use the Adobe PDF Print Engine. However, all of these RIPs should have no problem with fonts assuming that you submit a job with all fonts embedded, preferably a PDF/X-4 file.
If you want, contact me privately and we can look at the PDF file without the outlined text and see if in fact there is anything wrong with it at all.
- Dov