In article , "Richard D.
Saam" writes:

There is a question as to whether the "good upper (and lower) limits
on baryons from big-bang nucleosynthesis" must be modified
by high Z 'gold' collision experiments conducted inside
the Relativistic Heavy Ion Collider (RHIC),
an atom smasher at Brookhaven National Laboratory in Upton, New York.

Is there any evidence that this is relevant to BBN?

In order for it not to glow, it must be extremely cold
and if it were baryonic matter, how cold would that be?

Anything above absolute zero emits radiation. You can calculate the
intensity as a function of wavelength from the temperature (under
certain assumptions).

If dark matter objects had size dimensions on the order of meters,
then the dark matter galactic density on the order of 10^-24 g/cc
composed of these objects
would have a mean free path or optical density
such that they would not be optically visible under current methods

Right: back issue of the ApJ, or bricks. :-) Right, we don't know
whether it consists of microscopic objects, but if so, presumably it
would have to be self-interacting with a cross section much larger than
for the weak interaction.

The WIMP approach seems to be a dead end
based on negative experimental results
from the many current underground scintillation experiments.

Absence of evidence is not evidence of absence. Many particles were
predicted and discovered only years or decades later. In the case of
dark matter, it is not even clear what properties it must have, or at
least the range is much larger, so it is not easy to say where to look.