React Native Expo In App Purchase send custom variable to setPurchaseListener

Question

I am implementing In App Purchase function in Expo bare workflow using Expo-In-App-Purchase library. In their documentation it says you need to implement setPurchaseListener on a global scope.

That's currently how I have it set up in my App.tsx file:

// Set purchase listener
setPurchaseListener(async ({ responseCode, results, errorCode }) => {
    if (responseCode === IAPResponseCode.OK) {
        for (const purchase of results!) {
            if (!purchase.acknowledged) {
                const {
                    orderId,
                    purchaseToken,
                    acknowledged,
                    transactionReceipt,
                    productId,
                }: InAppPurchase = purchase;

                // in android, consumeItem should be set to false to acknowledge the purchase
                // in iOS this isn't needed because it's already specified in app store connect
                const consumeItem = Platform.OS === "ios";

                finishTransactionAsync(purchase, consumeItem).then(
                    (response) => {
                        //send call to back end
                    }
                );
            }
        }
    } else if (responseCode === IAPResponseCode.USER_CANCELED) {
        //Do nothing. User cancelled
    } else {
        console.warn(
            `Something went wrong with the purchase. Received response code ${responseCode} and errorCode ${errorCode}`
        );

        //catch all for all errors
        if (
            errorCode === IAPErrorCode.SERVICE_TIMEOUT ||
            errorCode === IAPErrorCode.SERVICE_DISCONNECTED ||
            errorCode === IAPErrorCode.SERVICE_UNAVAILABLE
        ) {
            showMessage(`Service unavailable (${errorCode})`, true);
        } else {
            showMessage(
                `Something went wrong with the purchase. Error code (${errorCode}). Please contact us with the error code if this persists`,
                true
            );
        }
    }
});

My question is if I have this defined in my App.tsx file, how is it possible to send a custom variable to my back end after a user purchases something? For example, someone can be in multiple leagues, they buy something for a particular league that they are in, how can I send the success back to my back end stating that the purchase was made for a particular league?

Would I just need to add multiple setPurchaseListeners? If that's so, is there a way to stop listening after a user navigates away from a page?