EXC_BAD_ACCESS on device, but works on a Simulator

Question

I had written a function below which is inside Framework A:

open func invokeTracking(key: String, bundle: Bundle? = Bundle.main) {

    let qos = DispatchQoS.QoSClass.default
    DispatchQueue.global(qos: qos).async {
        self.invokeAsyncTracking(key: String, bundle: bundle)

}

And I am calling this in an Xcode project in multiple places and also from other frameworks.

In Xcode project:

override func viewDidLoad() {
    super.viewDidLoad()
    HelperClass.invokeTracking(key: "Camino", bundle: Bundle? = Bundle.main)
}

Similarly calling it from Framework B

func callMainTracking() {
    super.viewDidLoad()
    HelperClass.invokeTracking(key: "Carthage", bundle: Bundle? = Bundle.main)
}

This is working fine and has worked for almost a year. Recently I added another additional default parameter to the invoke tracking method like this so as not to affect the existing method calls like below. And I am trying to set the value of this parameter of a global variable:

open func invokeTracking(key: String, bundle: Bundle? = Bundle.main, conventDict: [String: Any] = [:]) {
    
    mainDict = conventDict

    let qos = DispatchQoS.QoSClass.default
    DispatchQueue.global(qos: qos).async {
        self.invokeAsyncTracking(key: String, bundle: bundle)

}

The app is crashing in the main thread on the line mainDict = conventDict when trying to access that default parameter. If I do it inside the async its crashing in that async thread. But this crash is happening only when it's called from Framework B and not when its called from the Xcode project. Also this crash is happening only on the device.

I have tried the following to resolve this:

1. Tried to declare default parameter as optional and using if let to unwrap it.
2. Tried with different data types.
3. Tried by changing arguments order.

And the only way it does not crash is if I send a value for this default parameter from Framework B while calling this method.

func callMainTracking() {
    super.viewDidLoad()
    HelperClass.invokeTracking(key: "Carthage", bundle: Bundle? = Bundle.main, conventDict: ["test": "123"])
}

But this defeats the purpose of a usage of a default parameter. Im new to debugging Xcode crashes so any help would be appreciated.

I used the Instruments and tried to find a Zombie but there wasnt one. The app simply just crashed and no zombie process was detected.