Trying to use Newtonsoft.Json.Linq and System.Linq.Dynamic.Core

Question

What I want to accomplish is to check and see if a JSON-document conforms to a constraint and if so transform the document. Another requirement is that the constraints are user defined and I need to store them in a document database.

My initial thought was to use JSON-path for selecting the token that I want to test for. This proved to be impossible since JSON-path has no notion of siblings or parents. But, if I combine JSON-path with LINQ from json.net I can find a token by using SelectToken and then call Next to get the sibling which I can test in turn. An expression like that would also have the added benefit of being relatively easy for a user to configure via an UI and can be stored as a string in the document database.

So I tried to do a PoC and right away ran into a big issue that I'm not able to address. The example below is a abbreviated version of that PoC. What I'm trying to do is running System.Linq.Dynamic.Core and query a Newtonsoft.Json.Linq.JObject. I'm able to access properties but when I try to use SelectToken I get an exception.

If I run the following example:

using Newtonsoft.Json.Linq;
using System.Linq.Dynamic.Core;
using System.Linq.Expressions;

namespace DynamicLinqCore
{
    class Program
    {

        static JObject json = JObject.Parse(@"{}");
        static void Main(string[] args)
        {
            var exp = DynamicExpressionParser.ParseLambda(new ParameterExpression[] {
                Expression.Parameter(typeof(JToken), "jobj")
            },           
            typeof(JToken),
            "jobj.SelectToken(\"$\")");            
        }
    }
}

I get this:

System.Linq.Dynamic.Core.Exceptions.ParseException: 'No applicable aggregate method 'SelectToken(String)' exists'
Stack Trace:
   at System.Linq.Dynamic.Core.Parser.ExpressionParser.ParseAggregate(Expression instance, Type elementType, String methodName, Int32 errorPos, Boolean isQueryable) in C:\Users\Jonathan\Documents\GitHub\System.Linq.Dynamic.Core\src\System.Linq.Dynamic.Core\Parser\ExpressionParser.cs:line 1745
   at System.Linq.Dynamic.Core.Parser.ExpressionParser.ParseMemberAccess(Type type, Expression instance) in C:\Users\Jonathan\Documents\GitHub\System.Linq.Dynamic.Core\src\System.Linq.Dynamic.Core\Parser\ExpressionParser.cs:line 1623
   at System.Linq.Dynamic.Core.Parser.ExpressionParser.ParsePrimary() in C:\Users\Jonathan\Documents\GitHub\System.Linq.Dynamic.Core\src\System.Linq.Dynamic.Core\Parser\ExpressionParser.cs:line 744

By looking through the code for System.Linq.Dynamic.Core it looks like, since JObject implements IEnumerable, it won't try to look for a method. It just assumes that it should be a linq operator. I'm able to bypass this by implementing a wrapper class for JTokens that implement SelectToken and not the interface IEnumerable. This a really cumbersome workaround and I don't really want to do it this way.

Has anyone else run in to this problem and can provide a better solution or a workaround?