# get target directory path (this will change through each iteration of the utility)
$destination = "/abc/def/ghi/jkl" # this is a directory

`sudo -u UserB setfacl ....set group level perms on $destination` 

# is target direcory readable now
-r $destination
or
$newdestination = traverse backwards to next level (e.g. "/abc/def/ghi") 
run the sudo command to set the perms on $newdestination

Do the read test again on the original $destination
If successful finish 
otherwise
traverse back up the directory chain again and redo the setfacl and read test