A "loadable object" is a C library that the Perl module needs in order to do its work. To fix it, you probably need to run the following commands.
$ sudo yum install libxml2
$ sudo yum install libxslt
I'm surprised that these libraries are missing. How did you install the modules? If you used yum then they would have been installed as dependencies and if you used cpan (or cpanm) then Perl wouldn't have been able to build the modules without these libraries installed.
Update: I've just seen in another reply that you are installing this modules manually. Is there any reason why you're not using yum to install them?
$ sudo yum install perl-XML-LibXML
$ sudo yum install perl-XML-LibXSLT
