React Native iOS app crashes instantly after opening with "Can't get most elevated app state from dictionary"

I've created a React Native app using the XCode simulators which I'm now trying to test on an actual device. I've pushed my builds to Testflight and successfully installed it, however whenever I open the app and tap on the text input to enter my login details, the app closes instantly. I've installed the app on BrowserStack to get some more debugging information which gleaned this:

iPhone SpringBoard(KeyboardArbiter)[55] <Error>: HW kbd: Failed to set (null) as keyboard focus
iPhone mobilewatchdog[67] <Notice>: 1405846374958: id=@ pid=49428320, state=321
iPhone backboardd(IOKit)[59] <Notice>: Connection removed: IOHIDEventSystemConnection uuid:51F4150C-0C32-4F42-9B56-C0D2357D4477 pid:321 process:Groop type:Passive entitlements:0x0 caller:BackBoardServices: <redacted> + 368 attributes:<CFBasicHash 0x1028025a0 [0x102800010]>{type = immutable dict, count = 3,
iPhone backboardd(IOKit)[59] <Notice>: entries =>
iPhone backboardd(IOKit)[59] <Notice>:  0 : <CFString 0x100612960 [0x266187a30]>{contents = "pid"} = <CFNumber 0x91ab33ead8745a2b [0x266187a30]>{value = +321, type = kCFNumberSInt64Type}
iPhone backboardd(IOKit)[59] <Notice>:  1 : <CFString 0x1006240d0 [0x266187a30]>{contents = "bundleID"} = <CFString 0x100613180 [0x266187a30]>{contents = "bundleIdRedacted"}
iPhone backboardd(IOKit)[59] <Notice>:  2 : <CFString 0x100612390 [0x266187a30]>{contents = "HighFrequency"} = <CFBoolean 0x26618da10 [0x266187a30]>{value = true}
iPhone backboardd(IOKit)[59] <Notice>: }
iPhone backboardd(IOKit)[59] <Notice>:  inactive:0
iPhone SpringBoard(UserNotificationsServer)[55] <Notice>: connection invalidated
iPhone backboardd[59] <Notice>: [BKEventFocusManager] Setting foreground application to: (none) (-1)
iPhone ReportCrash(CrashReporterSupport)[322] <Notice>: Trying to create CR directory structure as root
iPhone SpringBoard(WiFiPicker)[55] <Notice>: WIFI PICKER [bundleIdRedacted]: isProcessLaunch: 0,    isForegroundActivation: 0,     isForegroundDeactivation: 1
iPhone symptomsd(SymptomEvaluator)[123] <Error>: Can\'t get most elevated app state from dictionary {
iPhone symptomsd(SymptomEvaluator)[123] <Error>:     BKSApplicationStateExtensionKey = 0;
iPhone symptomsd(SymptomEvaluator)[123] <Error>:     SBApplicationStateDisplayIDKey = "bundleIdRedacted";
iPhone symptomsd(SymptomEvaluator)[123] <Error>:     SBApplicationStateKey = 0;
iPhone symptomsd(SymptomEvaluator)[123] <Error>:     SBApplicationStateProcessIDKey = 321;
iPhone symptomsd(SymptomEvaluator)[123] <Error>:     SBApplicationStateRunningReasonsKey =     (
iPhone symptomsd(SymptomEvaluator)[123] <Error>:                 {
iPhone symptomsd(SymptomEvaluator)[123] <Error>:             SBApplicationStateRunningReasonAssertionIdentifierKey = Resume;
iPhone symptomsd(SymptomEvaluator)[123] <Error>:             SBApplicationStateRunningReasonAssertionReasonKey = 10000;
iPhone symptomsd(SymptomEvaluator)[123] <Error>:         }
iPhone symptomsd(SymptomEvaluator)[123] <Error>:     );
iPhone symptomsd(SymptomEvaluator)[123] <Error>: }
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: 321 bundleIdRedacted: Unknown (most elevated: Unknown)
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: Entry, display name bundleIdRedacted uuid (null) pid 321 isFront 0
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: Continue with bundle name bundleIdRedacted, is front 0
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: NBSM Current state: normal, changed: systemForeground to 0 for net type 0
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: bundleIdRedacted: Foreground: false
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: NBSM Eligible to go to broken
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: NBSM Current state: normal, changed: systemForeground to 0 for net type 0, eligible for broken but constraints unsatisfied (0,0)
iPhone symptomsd(SymptomEvaluator)[123] <Notice>: Failed to find process for bundleIdRedacted
iPhone ReportCrash(CrashReporterSupport)[322] <Notice>: cr_update: <private>

I've not been able to find out much about the Can't get most elevated app state from dictionary message other than this question, which doesn't seem relevant as I don't think I can deploy to TestFlight with a Developer certificate.