probleme de dates absentes updated / published

[scenaristeur]

tout juste installé un yeswiki en local avec cette extension,
c'est parfait pour envoyer des mises à jour sur un POD Solid https://bricodeurs.solidweb.org/public/activity/254e4ca0-c5ab-11eb-8bcd-b157bfa89688.json
mais les dates semblent ne pas passer correctement :

{
  "@context": [
    1
  ],
  "type": "Update",
  "to": [
    "http://127.0.0.1/yeswiki/?WikiAdmin/followers",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "actor": "http://127.0.0.1/yeswiki/?WikiAdmin",
  "object": {
    "id": "http://127.0.0.1/yeswiki/?FadA",
    "type": "1",
    "attributedTo": "http://127.0.0.1/yeswiki/?WikiAdmin",
    "to": [
      "http://127.0.0.1/yeswiki/?WikiAdmin/followers",
      "https://www.w3.org/ns/activitystreams#Public"
    ],
    "published": "TZ",
    "updated": "TZ"
  }
}

$data['data']

ne semble pas contenir les champs nécessaires :

'published' => format_date_xsd($data['data']['date_creation_fiche']),
'updated' => format_date_xsd($data['data']['date_maj_fiche'])

{
      "action": "edit",
      "user": "WikiAdmin",
      "text": "**MODIFICATION** Fiche \"fada\" de type \"Annuaire\" mise à jour par WikiAdmin\nhttp://127.0.0.1/yeswiki/?FadA",
      "data_type": "bazar",
      "bazar_form_id": 1,
      "data": {
        "bf_titre": "fada",
        "oldimage_imagebf_image": "FadA_capture-du-2021-05-23-21-12-33.png",
        "data-imagebf_image": "",
        "filename-imagebf_image": "",
        "bf_fonction": "boom",
        "bf_projet": " - spoggy\r\n - ipgs\r\n - bon-prix\r\n - ess-tables\r\n - contacts\r\n - -",
        "bf_tel": "",
        "bf_mail": "[email protected]",
        "bf_structure": "Spoggy",
        "bf_site_internet": "http://scenaristeur.github.io/ipgs",
        "bf_adresse": "",
        "bf_code_postal": "",
        "bf_ville": "Lyon",
        "bf_latitude": "45.7578137",
        "bf_longitude": "4.8320114",
        "antispam": "1",
        "id_typeannonce": "1",
        "id_fiche": "FadA",
        "semantic": {
          "@context": [
            1
          ],
          "@type": "1",
          "@id": "http://127.0.0.1/yeswiki/?FadA"
        }
      }