if you can't just 'thump on it and get it to work' then the plan of attack changes. Now you want to think about what parts you could substitue on each side to get a different result, to figure out what's going on.
source file: can you restore a different nearby file to that same directory under the same conditions? That might implicate a damaged backup file.
Destination directory:
Can you create NEW file with the same name in the destination directory? (Textedit can create a text file, then you can change its extension.)
Can you restore your backup file on top of that temporary file, over-writing the hand-created temporary file?
Can you restore your backup file, but to a different folder on the drive, or inside a new folder at that location?
these might indicate the folder is restricted or damaged somehow.
if you suspect a damaged directory, Disk Utility Repair disk is the guy who fixes those.