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C# MongoDB Add Item to Dictionary

To add an item to a Dictionary field in a MongoDB collection - say JoinRequests of the Ride collection - treat the dictionary field an array and utilize the $push operator. I do not like the k, v extra outlining, but this is the only way I found that works with dots in the key. If you find an atomic way that can treat the dictionary as a Document and not as an array of documents, please let me know.

Here is an example.

using Microsoft.Extensions.Options;
using MongoDB.Driver;

class Ride {
    // ..
    public Dictionary<Email, Passenger> Passengers { get; set; } = new();
    "Passengers": [{ "k": Email, "v": Passenger }]

public async Task<bool> AcceptJoinRequest(string rideId, string driver, string user) {
    var updatePull = Builders<Ride>.Update.Pull(r => r.JoinRequests, user);

    var update = updatePull.Update.Push(r => r.Passengers, new KeyValuePair<string, Passenger>(user, new Passenger()));

    var res = await _ridesCollection.UpdateOneAsync(x => x.Driver == driver && x.Id == rideId && x.JoinRequests.Contains(user), update);
    return res.IsModifiedCountAvailable && res.ModifiedCount > 0;