I don’t doubt that Democrats will try to add text that no “walls” be built. There is no way that 13 Senate republicans will agree to this text.
There are many more than that who are backstabbing NeverTrumpers and GOPe that will find a way to do so.
13 is not an insurmountable number given the composition of the Republican Senate. Lets see, Rubio, Alexander, Collins, Gardner, McConnel, Lee, Murcowski, Portman, Romney, Shelby, Sasse, Wicker, Ernst .......