I don't think the egg/dragon ideas are going to fly...
There seem to be only few people left who can read the old Moro script. AFAIK it's not based on pictograms as, for example, Chinese script.
Considering the cultural setting, I wouldn't expect to find obvious graphic references. Repetitions are much more likely to be tied to some numerological symbolism IMVHO. I'd guess that the inlay of this kris is also mainly talismanic but getting even approximate/tentative guesstimates for just about any questions regarding these and their underlying symbolism seems to be very difficult.
Regards,
Kai