I am guessing you don't know the history of the Star Sapphire...
So here's the TLDR version... In some continuities it contains the dormant Predator... You know... The embodiment of Love... Who's removal from the universe would, over the next few months, cause love to fade away.
Finally, Orange Lantern is not an expert on Emotional Spectrum technology. And the one time he attempted to contact the only group who would have been able to confirm whether the dormant Predator was inside the Star Sapphire he got chased away by giant fuck off beams.
You really, really need to stop bringing in every niche continuity from every corner of the DC verse as evidence. Zoat is using a very small selection of continuities, handpicking attributes from them, flat out writing his own continuity at some points, and ignoring or outright
denying the existence of others.
The fact that some continuity does X has about as much bearing on the story as the weekly temperature forecast in Liberia.
That aside, OL is a empath, and from what we've seen of embodiments they tend to be a bit...
energetic. When the Ophidian was sitting inside OL's ring, he had a few minutes until it
violently exploded from the strain. Not to mention that you could tell just by looking at it that there was a energy field inside it, and that energy field was
way bigger than anyone's head. And when the Ophidian took up residence in his lantern, it glowed intensely.
If the (primitive, compared to a power ring/lantern) Star Sapphire had the
Predator in it, it'd be glowing up a storm as indicated by
how embodiments and the storing thereof has been shown to work in ZOAT'S universe. Not to mention that, for a empath, it'd probably be a bit like staring into the sun. And
also not to mention, that, while working to build a containment system to safely channel its energy, OL and (IIRC) Constantine probably would've noticed things like "Holy shit, this crystal has enough power in it to
move planets!". And also
also not to mention that OL is experienced enough with Emotional Spectrum technology to build his own (admittedly crude) lantern as a demonstration.
Just because you haven't appealed to the relevant authority does not mean you can't be reasonably sure of something. I'm fairly certain my computer doesn't have any plutonium in it, but hey, I haven't checked with a nuclear regulator, so how would I know? It could be
filled with plutonium, even though I've opened it up a few times for maintenance and new parts. You never know!