I'm sorry for this non-issue but now I have no other mean to answer:
https://instantview.telegram.org/contest/elesquiu.com/template8/issue3/

The checklist states:
https://instantview.telegram.org/checklist#6-5-5-quotes
Quotes must be formatted to match their appearance in the source article, provided it is possible to identify them (and their type) in a reliable way. [...]

You have nothing to identify (normal or not), simply all blockquotes in the body (class="cuerpo-nota") are center aligned.
See the style rule in question: https://imgur.com/X4PnwAT

See these pages where even the normal blockquotes are center aligned:
https://www.elesquiu.com/sociedad/2019/3/8/cuidado-con-las-baldosas-podotactiles-del-centro-316656.html
https://www.elesquiu.com/espectaculos/2018/10/6/revivi-la-salsa-de-tres-de-laurita-fernandez-su-mama-en-bailando-2018-301169.html
https://www.elesquiu.com/espectaculos/2019/2/20/exponiendo-infieles-es-fake-revelan-estas-pruebas-sobre-badabun-315133.html
https://www.elesquiu.com/espectacul