AFter some additional tinkering and even more swearing... I've found that the Pane widget, doesn't actually act like a scrolled frame as the docs said. They apparently have a limit on how many scrolled widgets they can contain. That's why my example code works... and my actual code did not. I was able to bypass this problem by specifying a new frame for each scrolled widget in the pane. Is there a subroutine to get those 4 hours of my life back...?

my $p = $mw->Scrolled('Pane', -scrollbars => 'se',
                              -width=>'1200',
                              -height=>'850'
                              )->pack;

my $fr1=$p->Frame()->place(-anchor=>'nw',
                           -x=>"50",
                           -y=>"150");;
my $listbox1=$fr1->Scrolled('Listbox',
                              -scrollbars=>'e',
                              -exportselection => 0
                              )->pack;

my $fr2=$p->Frame()->place(-anchor=>'nw',
                           -x=>"50",
                           -y=>"150");
my $listbox2=$fr1->Scrolled('Listbox',
                              -scrollbars=>'e',
                              -exportselection => 0
                              )->pack;
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