This particular workflow is for Tech Refresh on a cDOT systems only. This workflow is not for 7mode to cDOT transition.
On cDOT systems, by default all the data volumes are cluster-mode volumes. But the vol0 volumes(node root volumes) are 7-mode volumes.
cDOT systems does support some special steps to create 7mode data volumes. But these volumes cann't be migrated with this Tech Refresh workflow.
In the pre-requisites section, we are mentioning about this limitation to migrate 7-mode data volumes on cDOT systems.
Currently WFA is not shipping workflow to transition from 7-Mode to cDOT. But I think similar workflows are already available on the community site.
Thanks and Regards,