onMomentumScrollEnd and OnIndexChanged not firing

On Windows 10

• react-native-swiper v1.5.12
• react-native v0.48.4

Oddly enough I have the same code on two pages, with just basic views, and on one it fires, and on the other it doesn't. I'm getting no logs for anything.

I can't fork the code because it's private, but this is the gist of the code.
Working code

render() {
  return (
    <View style={styles.container}>
        <Header title={this.state.title} onPress={()=>this.props.navigation.goBack()}/>
        <View style={styles.body}>
            <View style={styles.routes}>
              <Swiper loadMinimal={true} loadMinimalSize={4} showsPagination={false}>
                  {this.display()}
              </Swiper>
            </View>
            <View style={styles.alpha}>
                {this.displayAlpha()}
            </View>
          </View>
      </View>
  )

Not working code

onMomentumScrollEnd = (e, state, context) => {
    Reactotron.log(this.state.List[state.index].title)
    Reactotron.log(true, true)
}
render() {
  return (
     <View style={styles.container}>
       <Header title={this.state.title} onPress={()=>this.props.navigation.goBack()} navigate={this.props.navigation.navigate}/>
       <View style={styles.body}>
          <View style={styles.routes}>
             <Swiper loadMinimal={true} loadMinimalSize={4} showsPagination={false} onMomentumScrollEnd={this.onMomentumScrollEnd}>
                   {this.display()}
             </Swiper>
          </View>
          <View style={styles.alpha}>
            {this.displayAlpha()}
          </View>
        </View>
      </View>
  )
}

this.display() returns an array of basic like components.

Start by comparing the working and non-working render snippets, focusing on the Swiper onMomentumScrollEnd prop and the display() child array under React Native 0.48.4 and react-native-swiper 1.5.12 on Windows 10. Reproduce the missing callback with a minimal public example or inspect the Swiper callback entry point; done when the callback reliably logs the index in the affected setup.