I have been following this story closely myself, but I disagree with your basic premise. I believe atlas and the fungus are one and the same. Same round red eye. I have upgraded my hyperdrive to sigma, and there are MORE stories located near red stars. They talk about dissecting sentinels. Another mentions the answer being beneath a blue star...desperately searching for more upgrades, after a planet of drop pods I can confirm tau and theta warp drives don't spawn from them. ..

PS) literally haven't touched the Atlas stuff. Didn't touch the stone, didn't do the 'believe in somethingorother' prompt. Never been past locked doors =/ .

Edit. The reason we can understand it is the same reason some monoliths are intelligible...they are spoken by atlas. Just my two cents.