aggregation with group by, inner join and nested conditions in MongoDB

Question

First of all I am sorry if this is a basic question, I am new to queries in MongoDB. Well, what I need is to find the latest registers for a worker in my WorkerLocationContext document and the latest register for each sensor in my HeatMeasureContext document, then join it by their location and then apply some filters. Here are my Schemas:

HeatMeasureContext:

const heatMeasureContextSchema  = new mongoose.Schema({
    sensor: { type: Schema.Types.ObjectId, ref: 'MeasureSensor', required: true },
    humid: { type: Schema.Types.Number, required: true },
    globe: { type: Schema.Types.Number, required: true },
    mercury: { type: Schema.Types.Number, required: true },
    internal: { type: Schema.Types.Number, required: true },
    external: { type: Schema.Types.Number, required: true }
}, { timestamps: true })

MeasureSensor:

const measureSensorSchema = new mongoose.Schema({
    name: { type: String, required: true },
    description: { type: String, required: false },
    type: { type: String, required: false, uppercase: true,
        enumValues: ['MEASURE'], default: 'MEASURE' },
    location: { type: Schema.Types.ObjectId, ref: 'Location' },
    sensorType: { type: String, required: false, uppercase: true,
        enumValues: ['WORKER_ATTACHED', 'ENVIRONMENT'], default: 'ENVIRONMENT' },
    measurerType: { type: String, required: false, uppercase: true,
        enumValues: ['HEAT', 'RUID'] },
    placementType: { type: String, required: false, uppercase: true,
        enumValues: ['INTERNAL', 'EXTERNAL'], default: 'INTERNAL' }
})

WorkerLocationContext:

const workerLocationContextSchema  = new mongoose.Schema({
    sensor: { type: Schema.Types.ObjectId, ref: 'LocationSensor', required: true },
    worker: { type: Schema.Types.ObjectId, ref: 'Worker', required: true }
}, { timestamps: true })

Location

const locationSchema = new mongoose.Schema({
    name: { type: String, required: true },
    description: { type: String, required: false },
    type: { type: String, required: false, uppercase: true,
    enumValues: ['REST', 'ROOM', 'COURTYARD'], default: 'ROOM' }
})

Worker

const workerSchema = new mongoose.Schema({
    name: { type: String, required: true },
    workGroup: { type: Schema.Types.ObjectId, ref: 'WorkGroup', required: false }
})

I have built my query like this:

WorkerLocationContext.aggregate([ 
    {
        "$lookup": {
            "from": "HeatMeasureContext",
            "localField": "sensor.location._id",
            "foreignField": "sensor.location._id",
            "as": "HMContext"
        }
    },
    {
        "$match": {
            "$and": [
                { "$or": [
                    { "$and": [ 
                        { 
                            "HMContext.sensor.placementType": { "$eq": "INTERNAL" }}, 
                            {"HMContext.internal": { "$gte": limit} 
                        },
                        { 
                            "HMContext.sensor.placementType": { "$eq": "EXTERNAL" }}, 
                            {"HMContext.external": { "$gte": limit} 
                        },
                    ]},
                ]},
                { "WorkerLocationContext.worker.location.type": { "$ne": "REST" } }
            ]
        }
    },
    {
        "$group": {
            "_id": "null",
            "workers": {
              "$count": {}
            },
            "hmDatetime": {
                "$max": "$HMContext.createdAt"
            },
            "wlDatetime": {
                "$max": "$WorkerLocationContext.createdAt"
            }
        }
    }
]);

Basically, my goal with it is to count how many workers fit in that condition according to their current location, thus the latest registers in the context tables. I have tried some simulations in the mongoplayground, but nothing succeeded. Is it possible to be done in MongoDB? Can you help me?

Thanks in advance!