Added the Marketing package to our site running CMS 11.20.7 on .NET Framework 4.7.2. But after installing this on the developer machine I get the error

Could not load file or assembly 'System.Web.Http.WebHost, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference.

With a stackTrace pointing to EPiServer.Marketing.Testing:

[InitializationException: Initialize action failed for Initialize on class EPiServer.Marketing.Testing.Web.Initializers.TestingControllerInitialization, EPiServer.Marketing.Testing.Web, Version=2.6.10.0, Culture=neutral, PublicKeyToken=8fe83dea738b45b7]
   EPiServer.Framework.Initialization.InitializationEngine.InitializeModules() +812
   EPiServer.Framework.Initialization.InitializationEngine.ExecuteTransition(Boolean continueTransitions) +194
   EPiServer.Framework.Initialization.InitializationModule.EngineExecute(HostType hostType, Action`1 engineAction) +879
   EPiServer.Framework.Initialization.InitializationModule.FrameworkInitialization(HostType hostType) +226
   EPiServer.Global..ctor() +42
   Holmgrens.Web.EPiServerApplication..ctor() +37
   ASP.global_asax..ctor() +42

This is because the site is running version 5.2.6.0 but I have the assembly redirect.

<dependentAssembly>
      <assemblyIdentity name="System.Web.Http.WebHost" publicKeyToken="31bf3856ad364e35" culture="neutral" />
      <bindingRedirect oldVersion="0.0.0.0-5.2.6.0" newVersion="5.2.6.0" />
</dependentAssembly>

Is there some way to get this working on this solution?