It is not defined as a track reference. Either the ISOBMFF should list it explicitely as a possible track reference, or it should be removed from this list. It already correctly listed in the item reference list (https://mp4ra.org/#/item_references).
'iloc' is listed in the "track reference" category (https://mp4ra.org/#/track_references#) as follows:
It is not defined as a track reference. Either the ISOBMFF should list it explicitely as a possible track reference, or it should be removed from this list. It already correctly listed in the item reference list (https://mp4ra.org/#/item_references).