Securing a Generated PDF
Following the Digital download docs you may need the file path, so in order to get the file path in Enupal Snapshot you may need to return the asset model of the PDF:

{%  set settings = {
        filename: 'my-first-pdf.pdf',
        inline: false,
        asModel: true
    }
%}

{% set assetModel = craft.enupalsnapshot.displayTemplate("reports/pdf-report", settings) %}

{# Digital Download code #}
{% set token = craft.digitalDownload.createToken(assetModel, options) %}

&lt;a href="{{ craft.digitalDownload.url(token) }}"&gt;{{ assetModel.filename}}&lt;/a&gt;