PyQt /Windows: QtWebEngineWidgets fail to run with ANGLE

We're attempting to use QtWebEngineWidgets on the Desktop, but we're hitting the following error at runtime:

DXGI ERROR: CreateDXGIFactory cannot be called from DllMain. [ MISCELLANEOUS ERROR #76: ]
DXGI ERROR: CreateDXGIFactory cannot be called from DllMain. [ MISCELLANEOUS ERROR #76: ]
class QWindowsEGLStaticContext *__cdecl QWindowsEGLStaticContext::create(class QFlags<enum QWindowsOpenGLTester::Renderer>): Could not initialize EGL display: error 0x3003

The window hosting the widget then appears to be blank, or fails to appear at all. It appears that since, for QtWebEngineWidgets, the module's initialization method calls QtWebEngine::initialize(), this triggers the use of some of ANGLE's own initialization, which itself calls CreateDXGIFactory. However, according to Microsoft, this is illegal if called from DllMain: https://msdn.microsoft.com/en-us/library/windows/desktop/bb204862(v=vs.85).aspx

We believe this happens because PyQt dynamically loads QtWebEngine (likely through LoadLibrary). Is there a way to trigger QtWebEngine::initialize() at a later time?