Works for me with dummy objects:

test.pl:

#!/usr/bin/env perl

use 5.012;
use warnings;
use myDebugger;

my $instance = myDebugger::GetInstance();
say ref($instance);

$instance->{foo} = 'Persistent'; # Ensure we get same instance

my $instance_ref2 = myDebugger::GetInstance();
say ref($instance_ref2);
say $instance_ref2->{foo};
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myDebugger.pm:

package myDebugger;

use 5.012;
use warnings;

my $debugger;

sub GetInstance {
    return $debugger //= bless { foo => 'bar' }, 'OLEThingy';
}
1;
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Output:

OLEThingy
OLEThingy
Persistent
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I suggest you eliminate this code and focus on the object in question; boil it down to a small test case, and the problem might solve itself, or you can of course come back here armed with more information.