iOS端UnityAds通过AdMob mediation调用USRVWebViewCallback大量崩溃

多个iOS项目通过AdMob mediation接入UnityAds（未使用Unity引擎），近期突然出现大规模崩溃激增的情况，同时观察到EAFC等其他应用也存在该崩溃问题。

崩溃堆栈信息如下：

0  libobjc.A.dylib                0x2064 objc_retain_x0 + 16
1  libobjc.A.dylib                0x2064 objc_retain + 16
2  Game                           0xb2ac9c -[USRVWebViewCallback invoke:] + 7766960
3  Game                           0xb0f1c0 +[USRVApiSdk WebViewExposed_getSharedSessionID:] + 7653588
4  CoreFoundation                 0x20814 __invoking___ + 148
5  CoreFoundation                 0x1f860 -[NSInvocation invoke] + 428
6  Game                           0xb1e2c8 -[USRVInvocation nextInvocation] + 7715292
7  Game                           0xb2b4b4 -[USRVWebViewMethodInvokeHandler handleInvocation:] + 7769032
8  Game                           0xb2afd8 -[USRVWebViewMethodInvokeHandler handleData:invocationType:] + 7767788
9  Game                           0xb28644 -[USRVWebViewApp userContentController:didReceiveScriptMessage:] + 7757144
10 WebKit                         0xde8ac <redacted> + 236
11 WebKit                         0x1ee9c <redacted> + 680
12 WebKit                         0x1e788 <redacted> + 468
13 WebKit                         0x11f8ac <redacted> + 264
14 WebKit                         0x2a770 <redacted> + 44
15 WebKit                         0x24e30 <redacted> + 324
16 WebKit                         0x3a6e4 <redacted> + 520
17 JavaScriptCore                 0x5aa70 WTF::RunLoop::performWork() + 204
18 JavaScriptCore                 0x5b998 WTF::RunLoop::performWork(void*) + 36
19 CoreFoundation                 0x56834 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 28
20 CoreFoundation                 0x567c8 __CFRunLoopDoSource0 + 176
21 CoreFoundation                 0x54298 __CFRunLoopDoSources0 + 244
22 CoreFoundation                 0x53484 __CFRunLoopRun + 828
23 CoreFoundation                 0x52cd8 CFRunLoopRunSpecific + 608
24 GraphicsServices               0x11a8 GSEventRunModal + 164
25 UIKitCore                      0x40aae8 -[UIApplication _run] + 888
26 UIKitCore                      0x4bed98 UIApplicationMain + 340
27 Game                           0x433754 main + 234 (main.cpp:234)
28 ???                            0x1c5a7f154 (Missing)

当前临时解决办法是在AdMob控制台禁用UnityAds，但希望找到无需停用UnityAds的更好方案。同时因找不到合适的Unity反馈渠道，特此询问：是否有其他开发者遇到过相同问题？

内容的提问来源于stack exchange，提问作者Columbo