Implementing ssl pinning in a react-native application using TrustKit iOS

I'm trying to implement SSL pinning in a react-native application (RN 0.60) and I'm using Trustkit.

Following the guide posted in https://github.com/datatheorem/TrustKit these are the step that I've done:

1) Install TrustKit pod using pod 'TrustKit' and pod install

2) Added to my AppDelegate.m this piece of code:

#import <TrustKit/TrustKit.h>

//inside didFinishLaunchingWithOptions

NSDictionary *trustKitConfig =
  @{
    kTSKSwizzleNetworkDelegates: @YES,
    kTSKPinnedDomains: @{
        @"www.datatheorem.com" : @{
            kTSKEnforcePinning:@YES,
            kTSKIncludeSubdomains:@YES,
            //Using wrong hashes so it fails
            kTSKPublicKeyHashes : @[
                @"Ca5gV6n7OVx4AxtEaIk8NI9qyKBTtKJjwqullb/v9hh=",
                @"YLh1dUR9y6Kja30RrAn7JKnbQG/uEtLMkBgFF2Fuihh="
                ]
            }}};

  [TrustKit initSharedInstanceWithConfiguration:trustKitConfig];

When i try to do

 RNFetchBlob.fetch('GET', "https://www.datatheorem.com", {})    //tried using standard fetch() but gives same results
    .then(async(res) => {
        console.log('RES => ' ,res)
    })
    // Something went wrong:
    .catch((err) => {
        console.log('ERROR =>', err);
    })

It goes inside then and doesn't give any error but responds with a 200 status code (using wrong Hashes).

Otherwise, using Android it works correctly, going inside the catch and saying:

Error: Pin verification failed