The regular kris sword was the EDC and alter ego of any male Moro and, contrary to fairly late developments of keris culture on Java, was meant to be used if (perceived to be) needed. Not carrying a functional kris (or barung in Sulu regions) was akin to advertising being dumb enough to bring a toothpick to a swordfight. (To modify a common saying...
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I never heard that anyone attending formal Moro ceremonies was asked to put down arms or come with "toys" instead of the real thing (I guess this would have been regarded as severe insult to the guest as well as showing lack of courage on side of the host). A datu had retainers around him which certainly doubled up as bodyguards to deter unwise moves.
Like today with cars/etc., if someone had a high social status it wouldn't hurt to display a larger or more lavishly fitted sword than your rival on the other side of the mountain. Considering the materials (and longer scabbard) this is certainly a datu-level 'dress dagger' but I don't think it could double for the real thing in Moro culture for any but the youngest sons.
Older kids would wear kris not much smaller than typical ones; I've never seen one of those suggested to be children's kris with a blade distinctly shorter than the scabbard. A dagger (needing a completely different fighting style) would defeat the whole purpose though, I guess.
This configuration with the "oversized" scabbard would make most sense in a colonial setting after sword bans got into effect. However, this piece seems to predate this unfortunate period in Moro history by at least several decades.
To me it seems more probable to be a dagger meant to be worn in addition to a regular-sized Moro kris. Ron, could you please check whether you can see wear suggesting on which side this piece was actually carried?
Regards,
Kai