WPF ObservableCollection value type item Change

Question

I have many bool and string need to binding. So I write a IMultiValueConverter and binding like this:

        private ObservableCollection<bool> ischeckeds;

        public ObservableCollection<bool> IsCheckeds
        {
            get { return ischeckeds; }
            set { Set(ref ischeckeds, value); } //MvvmLight
        }

 class IndexToItemConverter:ImultiValueConverter
{
        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
        {
            
            if (values.Length ==2 )
            {
                if (values[0] is IList list )
                {
                    int index;
                    if (int.TryParse((string)values[1],out index)&& index < list.Count && index>=0)
                    {
                        return list[index];  
                    }
                }
            }
            return null;
        }
      
      ...
}

<local:IndexToItemConverter x:Key="indexToitemConverter" />
   <RadioButton>
 <RadioButton.IsChecked>
     <MultiBinding Converter="{StaticResource indexToitemConverter}">
         <Binding Path="IsCheckeds" />
         <Binding Path="Tag" RelativeSource="{RelativeSource Mode=Self}" />
     </MultiBinding>
 </RadioButton.IsChecked>
  </RadioButton>

SomeOne told me I have to use class to load the bool value type and implement INotifyPropertyChanged,like:

class Boolitem : ObservableObject //MvvmLight
{
        private bool ischecked;

        public bool IsChecked
        {
            get { return ischecked;}
            set { Set(ref ischecked;value); } //MvvmLight
        }
}

But if I use this way, My IndexToItemConverter couldn't be reused in (the Collection I don't need to NotifyPropertyChanged). cause it is binding in isCheck Porperty I have to take it in IndexToItemConverter

       public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
        {
            ...
                        return list[index].isChecked;  
            ...
        }

has a better ,more elegant anyone ? Thanks in advance