I understand that there are only two options

In core Perl, yes (Update: actually, autovivification isn't even in the core). But choroba showed one possibility, and writing a single-purpose routine isn't difficult either (I've admittedly compacted it a bit):

use warnings;
use strict;

sub dive { my $r = shift;
    $r = ref $r eq 'HASH' && exists $$r{$_} ? $$r{$_} : return for @_;
    return $r }

use Test::More;

my $h = { a => { b => { c => { d => 'e' } } } };

is dive($h, qw/ a         /), $h->{a};
is dive($h, qw/ a b       /), $h->{a}{b};
is dive($h, qw/ a b c     /), $h->{a}{b}{c};
is dive($h, qw/ a b c d   /), 'e';
is dive($h, qw/ a b c d e /), undef;
is dive($h, qw/ a x       /), undef;
is dive($h, qw/ a b x     /), undef;
is dive($h, qw/ a x y     /), undef;
is dive($h, qw/ a b x y   /), undef;
is dive($h, qw/ x         /), undef;
is dive($h, qw/ x y       /), undef;
is dive($h, qw/ x y z     /), undef;

is_deeply $h, { a => { b => { c => { d => 'e' } } } };

done_testing;
[download]

Update: Both of the links in your post appear to be broken. I assume you were trying to link to perl5280delta and RT#127712.

Thank you for code and making links good.

You've been given a solution by haukex in Re: 5.24 -> 5.28 -- what has changed in autovivification?.

Do you need more details? Here's an example:

#! /usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

use Data::Diver qw{ Dive };
use Data::Dumper;

my $h1 = {};
my $h2 = {a => {b => {c => 42}}};

for my $h ($h1, $h2) {
    say "Found $h->{a}{b}{c}" if Dive($h, qw( a b c ));
}
print Dumper $h1, $h2;
[download]

Found 42
$VAR1 = {};
$VAR2 = {
          'a' => {
                   'b' => {
                            'c' => 42
                          }
                 }
        };
[download]