Would you allow Disguise Self to do this?

[Jack Simth]

Well, the character in question both has knowledge local ranks (ie, for creature identification) and has lived among them (and has Illumian as one of his languages), so I see no issue in his ability to duplicate the sigils, and I never intended for the spell to give the benefits. Just you know, look real, and giving off light is important for that.

That said, how many of those above factors do you think would be needed for a person to make a decent duplication of the sigils with Disguise Self?

Presumably, in an area where such things are reasonably common, they'll be a reasonable number of people with reason to fake them. Which means there will be lots of people looking into how to do it.

The glow of a candle isn't all that much - modern times, we've got glowsticks that put out more than that for a few hours at a time... and they're just chemical reactions. Maybe require a proper disguise kit, and say you're applying alchemical substances that produce a glow. Or something. Just apply the penalty for disguising yourself as a different race, and you're good to go.