And by the way, passing result to XMLout produces original XML:

XMLout($xml, RootName => 'declaration');
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returns

<declaration dd:maxOccur="-1" dd:minOccur="0" dd:nullType="exclude">
  <contentDeclaration dd:minOccur="0" dd:nullType="exclude" />
  <value dd:minOccur="0" dd:nullType="exclude" />
</declaration>
[download]