For reference, here's how the OEM one lines up:
My TL-99 was slightly off, but the plus side was that it was much more snug than the factory HK handguard once installed. Only took a little bit of tapping with a nylon hammer(was amused to have the exact Picard hammer show in the TL-99 manual). Not bad overall for a part that really does not come off with any regularity.
Big thanks for the suggestion, fatman27!