Kickstart is an archive extraction tool whose current version 8.0.4. is compatible with JPA backup archive files generated by all versions of Akeeba Backup from 3.0.0 released back in 2010 up to and including 9.9.2 released four days ago. As someone who is using it multiple times a day during development to restore backups generated with various versions of Akeeba Backup for Joomla! 3, 4, and 5 I can assure you it will extract backup archives taken on Joomla! 5 just fine.
As a matter of fact, I just restored a Joomla! 5.1.0 backup I took on one dev machine onto another.
Do you have a backup? Can you download its files? If the answer to both questions is in the affirmative you can restore the backup archive file(s) using the process described in the Restoring a Site on Any Server video tutorial. While the video shows a Joomla! 3 site being restored, the process is identical for Joomla! 4, Joomla! 5, and even WordPress. We just had to show a backup archive of a site being restored for illustrative purposes. It wouldn't make business sense reshooting the same video with three different Joomla! versions, that's all there is to it.
Nicholas K. Dionysopoulos
Lead Developer and Director
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