PProHeadless executable embeds wrong/generic information in its serialized Info.plist
The Info.plist that is flattened and embedded inside the PProHeadless executable should have the same exact information as the Premiere Pro app, just so that third-party plugins can correctly identify their "environment". Instead, the flattened Info.plist embedded by the PProHeadless executable contains generic/wrong information. In particular, it has the incorrect bundle identifier, bundle version and signature:
CFBundleExecutable = PProHeadless;
CFBundleGetInfoString = "PProHeadless .., Copyright \U00a9 Adobe. All rights reserved.";
CFBundleIdentifier = "com.apple.product-type.tool";
CFBundleInfoDictionaryVersion = "6.0";
CFBundleName = PProHeadless;
CFBundleShortVersionString = "..";
CFBundleSignature = "????";
The PProHeadless executable appears to be launched to render projects via AME, as a background-only version of Premiere Pro (no UI ever presented). It appears that when you created the PProHeadless target in Xcode, you forgot to configure it so that it would have meaningful entries in its embedded Info.plist.
Please make sure that PProHeadless shares the same core CFBundle entries and values as the main Premiere Pro app. Some exceptions should stand, such as LSBackgroundOnly = 1, which is appropriate for a headless app. As it stands, the wrong Info.plist entries used by PProHeadless have unwanted side effects for a number of AppKit/Foundation APIs, such as NSBundle.
