Custom WixBA throws access denied in OnDetectPackageComplete when interrogating DetectPackageCompleteEventArgs.State parameter

[MikeFarrington]

I have a WPF-based bootstrapper that is being updated to the latest version of WiX Toolset.

In the OnDetectPackageComplete event, I can interrogate the PackageId from the DetectPackageCompleteEventArgs parameter just fine, but when I attempt to get the value from the State (PackageState) member, An access denied error is thrown. It gets logged twice, but I assume that is once in my UI thread, then it bubbles up to the host thread of the BA?

[1FB4:0618][2024-09-20T11:24:46]i000: (custom logging message) OnDetectPackageComplete for R441Redist: Finding BundlePackage
[1FB4:0618][2024-09-20T11:24:46]e000: Error 0x80004003: BA OnDetectPackageComplete failed.
[1FB4:1FA4][2024-09-20T11:24:46]e000: Error 0x80004003: BA OnDetectPackageComplete failed.