using System;
using System.Linq;
using System.Collections.Generic;
using System.Collections.Concurrent;
using System.Reflection;
using System.Linq.Expressions;
using System.Threading;
using System.Threading.Tasks;

var sync = new object();
var queue = new Queue<int>();
using var waiting = new ManualResetEventSlim();
int value = -1;
OwnedThreads.Run(
    () => { lock (sync) { waiting.Set(); while (queue.Count == 0) if (!Monitor.Wait(sync, TimeSpan.FromSeconds(5)) && queue.Count == 0) throw new TimeoutException(); value = queue.Dequeue(); } },
    () => { if (!waiting.Wait(TimeSpan.FromSeconds(5))) throw new TimeoutException(); lock (sync) { queue.Enqueue(7); Monitor.PulseAll(sync); } });
Console.WriteLine($"value:{value}");
Console.WriteLine($"remaining:{queue.Count}");

public static class OwnedThreads
{
    public static void Run(params Action[] actions)
    {
        var errors = new ConcurrentQueue<Exception>();
        var threads = actions.Select(action => new Thread(() => { try { action(); } catch (Exception error) { errors.Enqueue(error); } }) { IsBackground = true }).ToArray();
        foreach (var thread in threads) thread.Start();
        foreach (var thread in threads) if (!thread.Join(TimeSpan.FromSeconds(8))) throw new TimeoutException("Owned worker did not finish");
        if (!errors.IsEmpty) throw new AggregateException(errors);
    }
}