Good approach. You create a forensic master image or your storage media, maybe better a second copy of it, too.

You only work on a copy of that master image! Basic idea is to not have to touch old storage media a lot or at all anymore. Any procedure must not alter the forensic master image copy. You should always be able to easily get back to your initial data without risk of data loss if you need to start from fresh.

What do you know about your initial image copy?

Is the filesystem corrupted or OK?

Do you have to deal with deleted files? How much activity was there on the filesystem once important files were deleted or corrupted?

You would need to provide more details about your specific situation to be able to give you better advise on tools to recover wallet files.