http://cds.arbys.com/pdfs/nutrition/...Allrgn_MAR.pdf
And according to the Arby's website the reuben has 2560 mg of salt not 3480, and the turkey Rachel has 1850 not 3480. And those numbers include the cheese, sauerkraut and dressing.
While the numbers do not imply a low salt meal or even a healthy meal if you have any concerns with sodium, the figures from the OP which are claimed to be from the 800 number are not accurate according to the Arby's website.