Is there a possibility to perform an offline restore for ADAM databases?
Functionality to Offline restore of ADAM is missing in Recovery Manager for AD. Meanwhile you can perform restore using Extract Wizard.
If you look at Microsoft documentation (http://technet.microsoft.com/en-us/library/cc755780.aspx) you will see that ADAM actually being backed up and restored as simple set of files. Using Recovery Manager for AD extract Wizard you can get necessary files from backup and then replace existing files.