How to cite specific custom field with BibLaTeX?

Question

I am working on a document commenting another paper (Gödels incompleteness theorems). Therefore, I need two lists of bibliographies, one is mine and one the one from the other paper.

The other paper is quite old and uses different style'd citations. I want to keep the original paper as much as possible, so I want to create a custom field like:

@book{taocp1,
    keywords={own},
    author="Donald Ervin Knuth",
    title="The Art of Computer Programming, Volume 1",
    year=1968,
    isbn="978-0-201-89683-1"
}


@article{hilbertschebeweistheorie,
    keywords={goedel},
    goedeltitle={J.~v.~\so{Neumann}, Zur \so{Hilbert}schen Beweistheorie, Math. Zeitschr. 26, 1927.},
    year=1927,
    author="John von Neumann",
    title="Zur \so{Hilbert}schen Beweistheorie",
    journal="Mathematische Zeitschrift",
    number=26
}

Now, I know that I can have two bibliographies with things like

\printbibliography[keyword={own}] % Citations with keyword "own"
\printbibliography[keyword={goedel}] % Citations with keyword "goedel"

This works fine. But I need to cite the "goedeltitle" field to get the original string used for citing the work (but still have it cited normally in the second bibliography).

I tried

\citefield{hilbertschebeweistheorie}{goedeltitle}

and this gets the work cited in the second bibliography. But the text where goedeltitle is supposed to be only becomes hilbertschebeweistheorie in the PDF.

I'm using this command to load biblatex:

\usepackage[
    citestyle=authortitle-ibid,
    isbn=true,
    url=true,
    backref=true,
    backrefstyle=none,
    pagetracker=true,
    maxbibnames=50,
    defernumbers=true,
    maxcitenames=10,
    backend=bibtex,
    urldate=comp,
    dateabbrev=false,
    sorting=nty,
    ibidtracker=true
]{biblatex}
\bibliography{literatur.bib}