IIRC, the install-location used by cpanm (or cpan) is configured separately from the way that Perl itself knows where to look for libraries. Still, if one server is “the odd man out,” there could be several problems ... maybe just one source?
The most common determinant of the Perl search-path (perl -V) is the PERL5LIB environment variable, which is ordinarily set by a hidden script such as .bashrc on a Linux box; or by a registry setting on Windows. (I believe the System control-panel ... it’s per-user and/or global ... but don’t quote me.) Perhaps this file / registry entries are missing or different on this machine; perhaps they’re not being executed.
Free-thinking now ... if the root problem is that a script isn’t being executed such that environment-variables aren’t being set ... perhaps several of them aren’t being set ... which could explain many things simultaneously. Especially since, in the case of Unix/Linux, the file that contains these settings is usually hidden and not-required, its mere absence could manage much mischief.