How to load same assembly of different version in one application?

I have Windows forms application in C#. I am in need to make use of the below dll.

Interop.SHDocVw.dll

The problem is that I need to refer two different versions of this same assembly.

I tried keeping the dll in two different locations & tried to add but not allowing.

Following the below link, I tried to load two version of a assembly on runtime, but somehow not sure how do I do that.

https://www.codeproject.com/Tips/373589/Load-same-assemblies-with-different-versions

This is how my app.config looks like:-

<runtime>
<assemblyBinding  xmlns="urn:schemas-microsoft-com:asm.v1">
  <dependentAssembly>
    <assemblyIdentity name="Interop.SHDocVw.dll" publicKeyToken="db7cfd3acb5ad44e" />
    <codeBase version="1.1.0" href="...\watin-core\Interop.SHDocVw.dll"/>
  </dependentAssembly>

  <dependentAssembly>
    <assemblyIdentity name="Interop.SHDocVw.dll" publicKeyToken="632609b4d040f6b4" />
    <codeBase version="1.3.0" href="...\winforms\Interop.SHDocVw.dll"/>
  </dependentAssembly>

Currently the exception it is throwing:-

System.IO.FileLoadException: Could not load file or assembly 'Interop.SHDocVw, Version=1.1.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
 File name: 'Interop.SHDocVw, Version=1.1.0.0, Culture=neutral, 
 PublicKeyToken=null'
 at myApp.AppUI.InitializeComponent()

How do I address this?

as in http://geekswithblogs.net/narent/archive/2008/11/11/126940.aspx :

1) Edit your csproj file (right click on project in solution explorer , then unload project then, modify csproj file)

2) in this csproj file, add in ItemGroup containing Reference tags: (here an example with Office Interop 15 and 16)

<Reference Include="Microsoft.Office.Interop.Excel, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c">
  <HintPath>C:\Program Files (x86)\Microsoft Visual Studio\Shared\Visual Studio Tools for Office\PIA\Office15\Microsoft.Office.Interop.Excel.dll</HintPath>
  <Aliases>Test2</Aliases>
  <Private>False</Private>
</Reference>

and

<Reference Include="Microsoft.Office.Interop.Excel, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c">
  <HintPath>C:\Program Files (x86)\Microsoft Office\root\Office16\DCF\Microsoft.Office.Interop.Excel.dll</HintPath>
  <Aliases>Test1</Aliases>
  <Private>False</Private>
</Reference>

as you can see, I've added Aliases : Test1 and Test2

3)Then, reload project and in your .NET Code , add at the very first line of your code (before any "using"):

extern alias Test1;
extern alias Test2;

then in your code you can use the same assembly with 2 distinct versions:

Test1.Microsoft.Office.Interop.Excel.Application app1;
Test2.Microsoft.Office.Interop.Excel.Application app2;

Update 2019 dec 18 after comment from user203687 (I have downloaded your sample code and made it work with the app.config add-on below) : (adding a codebase reference solved the issue)

<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
  <dependentAssembly>
    <assemblyIdentity name="SampleLib" publicKeyToken="2901d9e7607fc6eb" />
    <codeBase version="1.0.0.0" href="YourFullPathTo\Lib-v1\SampleLib.dll" />
    <codeBase version="1.5.0.0" href="YourFullPathTo\Lib-v2\SampleLib.dll" />
  </dependentAssembly>
 </assemblyBinding>
 </runtime>