Repro steps for outbox issue

MassTransitReplyExceptionTest.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="MassTransit" Version="7.1.7" />
  </ItemGroup>

</Project>

Program.cs

using MassTransit;
using MassTransit.Saga;
using System;
using System.Threading;
using System.Threading.Tasks;

namespace MassTransitReplyExceptionTest
{
    class Program
    {
        public static async Task Main()
        {
            var busControl = Bus.Factory.CreateUsingInMemory(conf =>
            {
                conf.AutoStart = true;

                var machine = new SubmitOrderSaga();
                var repository = new InMemorySagaRepository<MyState>();
                conf.ReceiveEndpoint("saga", e =>
                {
                    e.StateMachineSaga(machine, repository);
                });
                conf.ReceiveEndpoint("saga-outbox", e =>
                {
                    e.UseInMemoryOutbox();
                    e.StateMachineSaga(machine, repository);
                });
            });

            var source = new CancellationTokenSource(TimeSpan.FromSeconds(10));

            await busControl.StartAsync(source.Token);
            try
            {
                while (true)
                {
                    string value = await Task.Run(() =>
                    {
                        Console.WriteLine("-------------------------------------------------\n\n\nPress 1 | 2 for Saga success/fail. Press 3 | 4 for Saga+outbox success/fail. Anything else to exit");
                        Console.Write("> ");
                        return Console.ReadLine();
                    });

                    if (value.Length == 0) return;
                    (string serviceAddress, bool? returnSuccessPlease) = value[0] switch
                    {
                        '1' => ("saga", true),
                        '2' => ("saga", false),
                        '3' => ("saga-outbox", true),
                        '4' => ("saga-outbox", false),
                        _ => ((string)null, (bool?)null)
                    };
                    if (serviceAddress == null) return;

                    var requestClient = busControl.CreateRequestClient<SubmitOrder>(new Uri($"queue:{serviceAddress}"), RequestTimeout.After(s:5));

                    try
                    {
                        var orderId = NewId.NextGuid();

                        Response response = await requestClient.GetResponse<OrderSubmitted>(new
                        {
                            OrderId = orderId,
                            ReturnSuccess = returnSuccessPlease
                        });
                        var resultId = response switch
                        {
                            (_, OrderSubmitted s) => s.OrderId,
                            _ => throw new Exception("Unexpected result")
                        };
                        Console.WriteLine($"Received a response of {resultId}");
                    }
                    catch (RequestFaultException e)
                    {
                        Console.WriteLine("FAULT EXCEPTION CAUGHT");
                        Console.WriteLine(e);
                        Console.WriteLine(e.InnerException);
                    }
                }
            }
            finally
            {
                await busControl.StopAsync();
            }
        }
    }
    public interface SubmitOrder
    {
        public Guid OrderId { get; set; }
        public bool ReturnSuccess { get; set; }
    }
    public interface OrderSubmitted
    {
        public Guid OrderId { get; set; }
    }
}

SubmitOrderSaga.cs

using Automatonymous;
using System;

namespace MassTransitReplyExceptionTest
{
    public class MyState : SagaStateMachineInstance
    {
        public Guid CorrelationId { get; set; }
        public string CurrentState { get; internal set; }
    }

    public class SubmitOrderSaga : MassTransitStateMachine<MyState>
    {
        public SubmitOrderSaga()
        {
            Event(() => SubmitOrder, c => c.CorrelateById(x => x.Message.OrderId));

            InstanceState(x => x.CurrentState);

            Initially(When(SubmitOrder).ThenAsync(async x =>
            {
                if (!x.Data.ReturnSuccess) throw new Exception("Saga fail");
                var ctx = x.CreateConsumeContext();
                await ctx.RespondAsync<OrderSubmitted>(new
                {
                    x.Data.OrderId
                });
            }).TransitionTo(Final));

            SetCompletedWhenFinalized();
        }

        Event<SubmitOrder> SubmitOrder { get; set; }
    }
}