_display.html.erb

<td><%= link_to transferred_from(call), call %></td>
<td><%= link_to transferred_to(call), call %></td>

calls_helper.rb

def transferred_from(call)
  if call.transferred_from?
    call.transferred_from.facility_name
  else
    call.transfer_from_other
  end
end

def transferred_to(call)
  if call.transferred_to?
    call.transferred_to.facility_name
  else
    call.transfer_to_other
  end
end
   

Cool. Yeah so normally you don't want to do this because you want to take the "happy path". Checking for nils is bad because that's the sad path first. Once you get more complex logic, that concept will begin to make a bit more sense.