i don't see
#!/usr/local/bin/perl -w
I know.. sounds retarded in something so simple.. but then..

this obviously means your object has not been made, made properly etc. so something is up with your %params, or the Net::SSH::Perl module, some dependency or something.. check the error log ofr the machine too! maybe the module is having an error or something else too.

I would suggest first eliminate every simple explanation, and i think even 'hello world' should -w