If 2.9.4 is no good, why is it being special-cased as the only version for which the build is allowed to proceed (under the particular encompassing circumstances) ?

Eh?

https://metacpan.org/source/SHLOMIF/XML-LibXML-2.0129/Changes 

2.0126  2016-06-24
    - Workaround RT#114638:
        - 2.9.4 broke XSD Schema support.
        - https://rt.cpan.org/Public/Bug/Display.html?id=114638
        - https://github.com/shlomif/libxml2-2.9.4-reader-schema-regression
        - https://bugzilla.gnome.org/show_bug.cgi?id=766834
        - https://github.com/shlomif/perl-XML-LibXML/pull/1
        - Thanks to Paul for the report and to RURBAN for a pull-req.
    - Add t/release-kwalitee.t for testing CPANTS Kwalitee.

In reply to Re^5: XML-LibXML-2.0129 installation issues by Anonymous Monk
in thread XML-LibXML-2.0129 installation issues by Brat

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