Submenu links not working on IOS

Hi all:
At https://infantproctocolitis.org, the “Health Professionals” menu has a submenu containing 2 links.
I used the script below (doubletaptogo by Osvaldas Valutis) to get the submenu to work on mobile devices, but on iOS, the links on the submenu do not work (works correctly on Android).
Anyone know how to fix this?
Thanks much.
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;(function( $, window, document, undefined )
{
	$.fn.doubleTapToGo = function( params )
	{
		if( !( 'ontouchstart' in window ) &&
			!navigator.msMaxTouchPoints &&
			!navigator.userAgent.toLowerCase().match( /windows phone os 7/i ) ) return false;

		this.each( function()
		{
			var curItem = false;

			$( this ).on( 'click', function( e )
			{
				var item = $( this );
				if( item[ 0 ] != curItem[ 0 ] )
				{
					e.preventDefault();
					curItem = item;
				}
			});

			$( document ).on( 'click touchstart MSPointerDown', function( e )
			{
				var resetItem = true,
					parents	  = $( e.target ).parents();

				for( var i = 0; i < parents.length; i++ )
					if( parents[ i ] == curItem[ 0 ] )
						resetItem = false;

				if( resetItem )
					curItem = false;
			});
		});
		return this;
	};
})( jQuery, window, document );