@sast Thanks for your patience, using devops resource kit you will not be able to get users and subscription key details as it is unique to each APIM instance. A better approach would be to use the backup and restore method. You can create a backup of your existing API Management instance and then restore it to the new instance. This will transfer all the content, including users and subscription keys, to the new instance.
Please refer: https://learn.microsoft.com/en-us/azure/api-management/api-management-howto-disaster-recovery-backup-restore?tabs=powershell
do let me know incase of further queries, I would be happy to assist you.