The issue is not so much humidity as it’s micro cracks. You can try annealing the PLA in an oven. Try it repeatedly, increasing the temperature by 5°C each time. Should be fine at the latest at 70-75°C, but this might also change the dimensions of the filament, making it unusable.
But filament is so cheap that it’s likely not worth the time and the electricity to try to fix small left-overs.
OpenAI is more efficient. Give a man a blanket and he will be warm for a winter. Give the world CO2 and there will be no winter.