What the page was built with is irrelevant. wpgraft reads the page as your browser rendered it: the real elements and the real computed styles on each one, at every width you ask for. It then builds that as Figma layers: frames, text, vectors and image fills, with auto layout wherever the page was genuinely laid out in rows and columns. Nothing that arrives depends on the original site still being there.
This is the “website to Figma” job: a page that exists as a live site, wanted as a design file. The usual way is a screenshot traced by hand, or an import that hands back one flat picture. wpgraft builds the page into your open Figma file from what the browser drew: frames, text you can retype, images as fills, and auto layout wherever the page was genuinely laid out in rows and columns.