The problem with "Sakka" in Lao Buddhism

A solution to a certain puzzle occurred to me today.

I had a few discussions in Laos (variously conducted in broken Lao &
broken English) wherein I was lectured that the Buddha was "the son of
god" --and, in at least two cases, this was told to me by ex-monks,
who had learned it from senior monks, and who insisted that this was
canonical.

From what they told me, and in response to a few questions, it was at
least clear to me that they did not mean "god" in the European sense,
nor Brahma, nor "the heavens" abstractly --but they meant a specific
god.

At the time, I had just alluded to the "standard biography",
incredulously, asking, in effect, didn't they know the Buddha's father
was a king -- a mere mortal.  On one occasion (viz., the only Laotian
I discussed this with who replied in English), this resulted in real
exasperation, as if to say, "No, not THAT father...".  This was even
more alarming to me, as it suggested both a heavenly father and an
early one (such as Joseph to Jesus, etc.).

Today, a simple solution to this occurred to me:

In Laos (if not in Thailand, also) they have been reading one of the
forms of /saakiya/ as if it were the proper noun /sakka/.  They are
mistaking the Buddha's clan-name (/sakka/, adjective) for the name of
Indra or Zeus (/Sakka/, noun).

Thus, the Buddha is taken for "the son of god", doubtless because of
adjective phrases such as /sakka-putta/.  It is quite possible that
this mis-reading emerged in the 20th century --I have no claims to its
ancient authenticity --and, while wisdom ages, ignorance is ever new.
I am not aware of any European scholar having ever made this mistake
(though it seems natural enough); perhaps this reflects how profoundly
un-grammatical the Lao (and possibly Thai) approach to the texts is,
viz., treating the structure of the language as if it were a string of
monosyllables.

I've never seen anything written on this, but I assume the common root
of /saakiya/ & /sokya/ is something like /sa/ + /okkaaka/ + /ya/ (the
latter lending some kind of passive or reflexive sound to it, rather
than another noun-ending?).  "Those who were well-descended from
/Okkaaka/"?

(The commentarial etymology, listed in M.'s Dict. of Proper Names, is:
_When Okkaaka heard of this, he praised their action, saying, "Sakyaa
vata bho kumaaraa, paramasakyaa vata bho raajakumaara; hence their
name came to be "Sakyaa"_).

E.M.