The Structured Data on Commons reconciliation service will ideally be hosted on Cloud-Services; either on Cloud VPS or Toolforge. https://en.wikipedia.org/wiki/Wikipedia:Wikimedia_Cloud_Services

We expect that the SDC reconciliation service will receive considerably less traffic than the Wikidata reconciliation service, and hence hosting externally will not be needed. Issues like T262553 and T262550 are less likely to arise.

We still need to figure out where, in the Wikimedia ecosystem, the best location for the SDC service would be though.