Just confirming - you are using the Classic Designer, correct?  (looking at your code, that's the assumption I am making, but you didn't tag your post either way).

I'm also assuming you have other code that is making the fields readonly and disabled based on the other radio button.

Based on those assumptions, my recommendation would actually be to tweak what you are doing when the radio button is modified.  Instead of making the fields both readonly and disabled, I find it's best to just make them readonly, and not disabled, in order to ensure the values save.

If you are actually making them read only from the Layout page, and then populating them with Javascript, you'll find that doesn't work to save the values.  In cases that I need to do that, I usually set them as Readonly in the Javascript instead of on the Layout page.  Like this (give any fields you want to obey this the javascriptReadOnly class): 

$(document).ready(function () {

  //make the javascriptReadOnly fields read-only - this has to be done via Javascript, 
  //not the Layout page otherwise the field values cannot be populated via Javascript.
  $('.javascriptReadOnly input').each(function() { 
    $(this).attr('readonly', 'true');
    $(this).removeClass('hasDatepicker');
    $(this).parent().find('.ui-datepicker-trigger').hide();
  });
  $('.javascriptReadOnly select').each(function() { 
    $(this).attr('readonly', 'true');
  });
  $('.javascriptReadOnly textarea').each(function() { 
    $(this).attr('readonly', 'true');
  });

});