Glottalic Geminate Stops

I posted this on the ZBB, but no one so far has been able to answer, so
I'm asking here too:

"I've seen a number of examples of languages that allow long or geminate
stops which have pulmonic egressive air stream mechanism, but before
today I hadn't seen any examples of languages which had long ejective or
implosive stops (ie ones with glottalic airstream mechanism). So I've
just been looking it up and Bole (a language in the same family as
Hausa, or maybe a dialect of Hausa?) seems to have at least some
examples of long implosive stops:

dó́ɓɓó ‘small pot for sauce’

However, what I've read suggests that Hausa glottalic stops like ɓ can
be realized as [b?] as well as [b_<] so I guess the ɓɓ could be [b:?] in
the above example. Since I'm not an expert on Hausa or Bole, I'm not
positive that this word is most commonly pronounced with a [b_<:] or not.
I still, though, haven't seen even any possible examples of long
ejective stops. So this is my question for the day: do you know any
languages that have geminate or long glottalic stops, either implosive
or ejective, and how common are they? And if you know Bole (or Hausa),
is the above a true example of a long implosive, and do the ejectives in
the same series also have long variants?"

Next Message:

"Continued googling has uncovered another possible example, from Endegen
(Semitic):

k’ɨrəkk’ərə

the paper seems to suggest that the medial kk' is a long ejective stop."

So anyone who knows anything about a language that definitely has long
ejective or implosive stops that contrast with short versions of the
same stop, please post it, with examples?