Q:

How does the Hashalaq Quori's Disguise Self spell work?

The Hashalaq Quori is an aberration that looks very different from the humanoids that typically get access to the disguise self spell.  It is unclear to me what forms are available to them when they use this spell.
The key restriction from the spell is:

You can't change your body type, so you must adopt a form that has the same basic arrangement of limbs.

But the hashalaqs have no "basic arrangement of limbs":

In their natural form, hashalaqs are composed of hundreds of translucent tendrils. They can compress and configure these tendrils to form a wide range of simple shapes.

Furthermore, the creatures don't have the line of text that allows the lamia, for example, to use humanoid forms.
How, then, should this ability be interpreted?  Can the hashalaq reconfigure its natural form to be humanoid in shape, allowing it to take the form of a humanoid with disguise self?  Can it only transform into a different-looking amorphous creature?  Or is there a different interpretation that works better here?

A:

It is hard to speak for the developer, but it seems clear from one of the quotes:

They can compress and configure these tendrils to form a wide range of simple shapes.

I would interpret that this provides any simple arrangement of limbs the Hashalaq might need for a successful disguise self.
Strict reading of the spell would prohibit this, but I would say the flavor text is intended to allow it.
Another interpretation might look ar their Possession action and rule that the disguise is only intended for when they possess another body (unless that prevents them from spellcasting innately), since there is probably no other creature with the same arrangement of limbs. This would be very limited, in my opinion.
Comparing it with the Lamia does point more towards this limitied interpretation, but that is assuming the rules are written consistently across all the books.

