I mean barely anyone can read and decipher poneglyphs...
The question is why does it need a specific route- is it in a specific place? Does it require special procedures?
Why are the poneglyphs needed to find it?
If it's just some mysterious Island, then you can opt for option 4. It's just an island that's really hard to find.
I see what you're saying, though. Laughtale is supposed to be at the end of the log poses as the final island, and that the trial of even getting there is supposed to make it challenging.
To elaborate, I'm questioning the circumstances surrounding why the log poses stop. Explanations for that can include (1) it produces no EM signature for the log poses to recognize (2) the location itself is outside of the range of log poses (3) simply nobody ever used log poses there.
It is a good idea to discuss the differences with log poses and which ones are used in the New World at this point.
New World Log Pose
Design: Features three needles instead of one.
Why Three?: In the New World, some islands randomly change or completely hide their magnetic fields. If you only had one needle and that island's field vanished, you would be stranded.
The way people navigate the New World, and why the Laughtale Island hasn't been discovered can relate to the mechanics involved and the absence of evidence.
It's also useful to note what Roger's experience was upon reaching Lodestar Island.
When Gol D. Roger reached Lodestar Island—the final point on the standard Log Pose path—the needles on his Log Pose began spinning indefinitely and failed to point to any further island.
An interesting thing about this is that Roger was effectively stranded if that was his only log pose. All three needles went out of sync, and that implies that any islands they were pointing to either changed their magnetic fields or they were completely hidden.
It's also important to cite precedent with previous examples.
Malfunctions with Log Poses
Pointing Straight Up (Jaya/Skypiea): Right after leaving Alabasta, the Log Pose needle pointed directly toward the sky. Nami initially thought it was broken or malfunctioning, but Nico Robin explained it was actually working perfectly—it had locked onto a Sky Island (Skypiea).
Spinning Wildly (Twin Capes): When the Straw Hats first entered the Grand Line, Nami’s standard compass began spinning uncontrollably. This wasn't a mechanical failure but a reaction to the Grand Line's unique magnetic fields, which eventually led to Crocus giving them their first Log Pose.
The "Jiggling" Needles (New World): In the New World, Luffy's three-needle Log Pose often has one or more needles shaking or vibrating erratically. While this looks like a malfunction, it actually indicates that the island's magnetic field is unstable or dangerous. Luffy famously prefers to follow whichever needle is "acting up" the most because it usually leads to the biggest adventure.
The specific "spinning indefinitely" that Roger experienced happens only at Lodestar Island, the final island reachable by magnetism. Since Luffy has been following specific paths or jumping between islands using Vivre Cards and Eternal Poses (like the ones for Dressrosa or Zou), he hasn't reached that ultimate magnetic dead-end yet.
What seems likely is that the phenomenon that Roger observed in his Log Pose was not a malfunction, but rather it was locking on to Laughtale. The spinning continuously happened because Laughtale produces a volatile magnetic field. However, it was there if it was functioning properly.
If it was up, in the sky, or down, in the sea, then the Log Pose would simply point that way.
A case of spinning uncontrollably occurred when the Straw Hats entered the Grand Line due to volatile magnetic fields. 
