It was the hottest temperature achieved but the dewpoint barely made it above ambient, so the filament is probably dry enough to print.  The lion kingdom wants to know where it maxes out.  The inside temperature always has an inflection point, probably when sunset happened.

The AHT20 is rated for +/-6% humidity when temperature is 60C, so not surprisingly it appeared to clamp at 4% at 57C.  It's probably intended for habitable ranges instead of industrial ranges.  

The internet doesn't know what dew point to expect from common dessiccant.  Dew points in the flyover states are -10C in winter.  Dew points for the water in rocket fuel are -60C.  -60C is 7 parts per million by weight.  When the filament is fully hydrated at night, the -18C dew point is 770 parts per million by weight.  Calif*'s typical 4C ambient dewpoint is 4000 parts per million by weight.

It seems the lion kingdom will need another container & desiccant for PETG.