new partition will not mount outside ddrescue-gui

Failing drive - 1.5 TB partition on a 3 TB drive
Rescue drive - 1.5 TB partition on a 4TB drive
OS - MacOSX 10.10.5
I used ddrescue-gui with from and to both set to partitions. I think this may have been my mistake. Anyway, the rescue finished with only 6 errors and it let me mount it with ddrescue-gui. Everything I tried (not much, but whatever) worked fine. Then I quit ddrescue-gui and tried to mount the new partition with disk utility and it refused, then I tried repairing the new partition with disk utility (results attached at the end of this) What I'd really like is to mount this new one however ddrescue-gui did and copy off whatever I can through finder. Is that possible? Is there a better plan? Do you need more info? Any help is appreciated.

Thanks for reading - Jerry

Output of repair from disk utility:

Verify and Repair volume “Watkins”Repairing file system.Checking Journaled HFS Plus volume.Invalid B-tree node sizeThe volume could not be verified completely.File system check exit code is 8.Updating boot support partitions for the volume as required.Error: Disk Utility can’t repair this disk. Back up as many of your files as possible, reformat the disk, and restore your backed-up files.