Can't decipher this symbolicated crash log - ios

Question

Note: please don't mark this question as a duplicate, as I've searched the other similar questions but they are slightly different.
After submitting my app for review, it was rejected after it crashed on the app's first screen on an iPad Mini (iOS 11.2). This screen is just a basic registration page, and the app has never been rejected during review any time previously (and the page wasn't recently updated either). Unfortunately I don't have an iPad Mini, and I haven't experienced any crash in my simulator or physical iPhone devices.
Here is the reason for the crash (from what I've gathered, its most likely due to trying to access a variable that no longer exists in memory):
Exception Type: EXC_BAD_ACCESS (SIGKILL)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000020
And here is the thread that crashed:
Thread 0 name: tid_303 Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libobjc.A.dylib 0x00000001820fc1a0 objc_retain + 16 (objc-object.h:440)
1 AXRuntime 0x000000019249ee00 _AXElementForAXUIElementUniqueId + 208 (AXSimpleRuntimeManager.m:0)
2 AXRuntime 0x000000019249ed08 _UIAXElementForAXUIElementRef + 48 (AXSimpleRuntimeManager.m:402)
3 UIAccessibility 0x000000019427ae98 -[NSObject(UIAccessibilityAutomation) _accessibilityUserTestingSnapshotDescendantsWithAttributes:maxDepth:maxChildren:maxArrayCount:] + 1444 (UIAccessibilityAutomation.m:593)
4 UIAccessibility 0x000000019427cf08 -[NSObject(UIAccessibilityAutomation) _accessibilityUserTestingSnapshotWithOptions:] + 640 (UIAccessibilityAutomation.m:779)
5 UIAccessibility 0x0000000194250268 -[NSObject(AXPrivCategory) accessibilityAttributeValue:forParameter:] + 8836 (NSObjectAccessibility.m:4304)
6 UIAccessibility 0x000000019422fc80 _copyParameterizedAttributeValueCallback + 224 (UIAccessibilityRuntime.m:752)
7 AXRuntime 0x00000001924a6ad0 ___AXXMIGCopyParameterizedAttributeValue_block_invoke + 100 (AccessibilityPriv.m:1128)
8 AXRuntime 0x00000001924a6238 _handleNonMainThreadCallback + 60 (AccessibilityPriv.m:363)
9 AXRuntime 0x00000001924a6924 _AXXMIGCopyParameterizedAttributeValue + 344 (AccessibilityPriv.m:1127)
10 AXRuntime 0x00000001924a1220 _XCopyParameterizedAttributeValue + 380 (AccessibilityClientDefsServer.c:1160)
11 AXRuntime 0x00000001924b328c mshMIGPerform + 252 (MachServerHelper.c:448)
12 CoreFoundation 0x0000000182e3fe00 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 56 (CFRunLoop.c:1998)
13 CoreFoundation 0x0000000182e3f504 __CFRunLoopDoSource1 + 440 (CFRunLoop.c:2135)
14 CoreFoundation 0x0000000182e3cfd8 __CFRunLoopRun + 2196 (CFRunLoop.c:3150)
15 CoreFoundation 0x0000000182d5cc58 CFRunLoopRunSpecific + 436 (CFRunLoop.c:3245)
16 GraphicsServices 0x0000000184c08f84 GSEventRunModal + 100 (GSEvent.c:2245)
17 UIKit 0x000000018c4b55c4 UIApplicationMain + 236 (UIApplication.m:3956)
18 MyAppiOS 0x0000000102346db0 wrapper_managed_to_native_UIKit_UIApplication_UIApplicationMain_int_string___intptr_intptr + 16494000 (/<unknown>:1)
19 MyAppiOS 0x00000001022b764c UIKit_UIApplication_Main_string___intptr_intptr + 15906380 (UIApplication.cs:79)
20 MyAppiOS 0x00000001022b760c UIKit_UIApplication_Main_string___string_string + 15906316 (UIApplication.cs:63)
21 MyAppiOS 0x00000001013bfc84 MyApp_iOS_Application_Main_string__ + 212100 (/<unknown>:1)
22 MyAppiOS 0x00000001016fd204 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 244
23 MyAppiOS 0x0000000103297148 mono_jit_runtime_invoke + 32551240 (mini-runtime.c:2768)
24 MyAppiOS 0x00000001032fe574 do_runtime_invoke + 32974196 (object.c:2862)
25 MyAppiOS 0x00000001033010e4 do_exec_main_checked + 32985316 (object.c:4690)
26 MyAppiOS 0x000000010327fb90 mono_jit_exec + 32455568 (driver.g.c:1036)
27 MyAppiOS 0x0000000103392da8 xamarin_main + 33582504 (monotouch-main.m:0)
28 MyAppiOS 0x00000001013bf178 main + 209272 (main.m:203)
29 libdyld.dylib 0x000000018287c56c start + 4
And then there are thousands of lines similar to these in the symbolicated crash log:
UIAccessibility: Trying pt: {660.00001764298941, 512.00013971327644}
UIAccessibility: Hit testing found: UIAccessibilityPickerComponent [0x127e7cba0] (null) {{0, 514.5}, {1024, 291}}
UIAccessibility: Is descendant of desired element
UIAccessibility: Received visible point {512, 660} for <UIPickerView: 0x1279d5da0; frame = (0 99; 1024 216); clipsToBounds = YES; layer = <CALayer: 0x1279d5d70>>
UIAccessibility: Checking visibility for UIAccessibilityPickerComponent [0x127e7cba0] (null) {{0, 514.5}, {1024, 291}}
UIAccessibility: Trying pt: {660.00001764298941, 512.00013971327644}
UIAccessibility: Element matched start element
UIAccessibility: Received visible point {512, 660} for UIAccessibilityPickerComponent [0x127e7cba0] (null) {{0, 514.5}, {1024, 291}}
UIAccessibility: Did post notification. notification: (4002) error:0 data:{
event = AnimationsNonActive;
}
UIAccessibility: Did post notification. notification: (4002) error:0 data:{
event = RunLoopIsIdle;
}
UIKit: NavBar: set identifier (null) <UINavigationBar: 0x1279ad2f0; frame = (0 20; 1024 96); autoresize = W; tintColor = UIExtendedSRGBColorSpace 0 0.478431 1 1; layer = <CALayer: 0x1279a4490>>
UIKit: NavBar: top most item <<UINavigationItem: 0x127b9ab00>: title:'Register'> <UINavigationBar: 0x1279ad2f0; frame = (0 20; 1024 96); autoresize = W; tintColor = UIExtendedSRGBColorSpace 0 0.478431 1 1; layer = <CALayer: 0x1279a4490>>
// Note: the line above is the last line that is shown, before showing the crashed thread information
I really don't know what to make of this log. I even checked any other callback methods that may be taking place during the time the first screen is shown, but I just can't figure it out (especially when I can't even get it to crash on my end). Any help would be really appreciated.