in reply to JSON and Perl Objects - How to access data?

The structure is a hashref that contains a single member with key "items" which consists of an arrayref that contains two hashrefs. So you have to dereference the arrayref to get its members something like this:
for my $item( @{$inventors_object->{items}} ){ print $item->{name} . "\n"; };
To change the data:
$inventors_object->{items}->[0}->{name} = 'new name';
To turn it back into a JSON string:
my $new_json = objToJson( $inventors_object );
update here is your mistake:
@inventors_array = $inventors_obj->{"items"};
You are trying to turn an arrayref into an array without dereferencing it. Instead you want:
@inventors_array = @{ $inventors_obj->{"items"} };