A lot of learning came out of this thread for me, and I appreciate everyone that has contributed through posts and through /msg. I found that the passing the hash within the subroutine directly corrected the problem. So rather than a reference

my $new_session = Net::SNMP->session(\%options);
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just passing the hash itself works

my $new_session = Net::SNMP->session(%options);
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My next step will be taking out those unnecessary quotes and cleaning up the code with the suggestion I've received.

thanks -c