Another cleaner variant that works with the initial data structure.

my @aoh = ( 
    {k0 => 'v0' }
  , {k1 => 'v1' }
  , {k2 => 'v2' }
  , {k3 => 'v3' }
);

my ($val) = grep {exists $_->{k2}} @aoh;
$val &&= $val->{k2};
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