dynamic references by sending it from the route - node.js

Question

I have been looking at the documentation and some other questions made, but I have not been able to do it, I need to consult another collection for an objectId, but these collections come dynamically in the routes.
The collections come req, as they are from many different clients
https://mongoosejs.com/docs/populate.html
//route
// example collection dynamic ssdf2451_users, ssdf2451_campus, ssdf2451_programs
router.get('/school/prueba/tipos/', async (req, res, next) => {
let users
let school
let prueba
try {
const Users = model(`ssdf2451_users`, UserSchema)
console.log(Users)
await Users.findOne({ _id: '5ef56f70d19aea6e70c82a50' })
.populate('schoolId')
.exec(function (err, usersDocuments) {
console.log(usersDocuments, err)
// handle err
prueba = usersDocuments
res.status(200).json(prueba)
})
} catch (err) {
next(err)
}
})
// Schema
import { Schema, model } from 'mongoose'
const UserSchema = new Schema({
state: {
type: Boolean,
default: false,
required: false
},
accountNumber: {
type: Number,
required: false
},
schoolId: {
type: Schema.Types.ObjectID,
required: true,
ref: 'schools'
},
campusId: {
type: Schema.Types.ObjectID,
required: true,
ref: dynamic
},
programsId: {
type: [Schema.Types.ObjectID],
required: false,
ref: dynamic
},
})
const User = model('users', UserSchema)
export { User, UserSchema }