Hi Daniel,
You should be able to use the DART module but it is generally recommended that you use the same version of Anyconnect client and DART.
If there isn't any specific reason, you should consider upgrading client to a newer version as they have multiple vulnerabilities addressed.
Thank you,
Dinesh Moudgil
P.S. Please rate helpful posts.
Cisco Network Security Channel - https://www.youtube.com/c/CiscoNetSec/