Heres a more useful answer:
Arrapago II was the RMT hotspot as well as the hotspot of people cheating to farm alexandrite. There was a way to go back to 5f and repeatedly farm the Gears that pop from the Ramparts that are guaranteed one alex. This only worked in Arrapago (or atleast was the only area worth doing it in), and instead of SE fixing the problem at the root cause, they issued a one day lockout (or maybe they also fixed the problem, I'm not risking it to find out). Theres no reason for this lockout to still exist in 2024, nor has there been any reason for said lockout since the implementation of Ambuscade.
For whatver reason, I dont believe this exploit worked on the last boss that was guaranteed a Linen.