If you're working on a Tablet PC, then OneNote can work with Ink (note the
uppercase which indicates the Tablet-specific data type). If you're not on a
Tablet PC, none fo the suggestions below will work, as OneNote requires the
Ink API to perform its text conversion. Anything that you "write" on a
normal PC with a mouse or other digitizer device will be treated by OneNote
as a picture, and cannot be converted to text or searched.
When handwriting is placed on the clipboard from OneNote, a conversion of
that text is also placed, and can be selected from Edit | Paste Special in
the target application. So you could conceivably make your interview notes
in OneNote on a Tablet then copy and paste pieces of that text into your PDF
form.
There's another solution which may be more work short term, but would
undoubtedly pay off longer term. Why use OneNote at all? If your goal is to
handwrite into a PDF form, maybe you or someone in your company with
programming skill use the Ink API to provide the data entry directly into
your PDF form. You could also use the Tablet Input Panel to write and then
insert into the PDF.