relink … {look for broken links in this folder: true}

-- I've never seen that UI feature scripted, so I always use something like this:

set newFD to "HardDrive2:Links-New:" -- new source folder of links

tell application "Adobe InDesign CS6"

  tell document 1

  set eflag to 0

  try

  set myBrokenLinks to object reference of (every link whose status is link missing)

  on error

  display dialog ("No missing links found.")

  set eflag to 1

  return

  end try

  if eflag = 0 then

  set oldTIDs to AppleScript's text item delimiters

  set AppleScript's text item delimiters to ":"

  repeat with i from 1 to count of myBrokenLinks

  set oldFP to (file path of item i of myBrokenLinks) as string

  set newFP to (newFD & (last text item of oldFP)) as string

  relink item i of myBrokenLinks to alias newFP

  end repeat

  update every link

  set AppleScript's text item delimiters to oldTIDs

  end if

  end tell

end tell