Since Perl modules are only files, I don't see how merely adding files that are not used now would degrade the performance of non-Perl programs.

Maybe there is a miscommunication between you and the administrator of the Informatica program/machine. Maybe the administrator means that running Perl programs on the machine will degrade the performance of Informatica. This could easily be true as there only is a finite amount of CPU and other resources which Informatica would need to share with other programs.

Maybe also the administrator does not want to do the extra work needed for installing modules.

My suggestion to you is to talk again with the administrator and find out their true motivation.

If the objection is that the machine does not have enough power for additional processes, you could find another machine to run your processes on.

If the objection is that the administrator does not want (or know) to install the modules you could offer help there or install the modules in a private directory together with your program. See local::lib and Yes, even you can use CPAN.