How can I, in org-mode, reference another heading in a different file in the same directory please?

For example -

--8<---------------cut here---------------start------------->8---
* Testing
** Testing number one
:mydrawer:
See \uline{Testing number one} on page \pageref{fu2:2c2a0555-27a4-4ac1-b124-ffb60ee2af00}
:END:
\label{2c2a0555-27a4-4ac1-b124-ffb60ee2af00}
--8<---------------cut here---------------end--------------->8---

Is in /home/boudiccas/research/writing/fu/fu2.org

and I want the reference to appear in the org-mode file in '/home/boudiccas/research/writing/fu/fu.org'

And show as -

--8<---------------cut here---------------start------------->8---
* Testing
** testing one

# See \uline{Testing number one} on page \pageref{{fu2.org}:{2c2a0555-27a4-4ac1-b124-ffb60ee2af00}

# See \uline{Testing number one} on page \pageref{{fu2.org}:2c2a0555-27a4-4ac1-b124-ffb60ee2af00}

# See \uline{Testing number one} on page \pageref{fu2.org:2c2a0555-27a4-4ac1-b124-ffb60ee2af00}

# See \uline{Testing number one} on page \pageref{fu2:2c2a0555-27a4-4ac1-b124-ffb60ee2af00}

# See \uline{Testing number one} on page \pageref{2c2a0555-27a4-4ac1-b124-ffb60ee2af00}

--8<---------------cut here---------------end--------------->8---

Both files are exported to latex and built into a pdf file.

In the second example I have tried various things, including

--8<---------------cut here---------------start------------->8---
# #+latex_header: \include{/home/boudiccas/research/writing/fu/fu2}

# #+latex_header: \input{/home/boudiccas/research/writing/fu/fu2.org}
--8<---------------cut here---------------end--------------->8---

but none were successful.

So everything that I have tried, and fails, is commented out.

So how can I do it please? Is it actually possible to do it?

Thanks
Sharon.
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