Wolverines are vicious little *******s, but honey badgers will eat ANYTHING. I say honey badgers are tougher, stick with the honey badger.
Caleth will go second, I guess. At its largest, the well system is large enough for two people to walk abreast and for the tallest characters to walk normally; the taller characters(Calethen, Jozan, Siber, Felp) will probably have to duck down about 50-75% of the time, and you should also be ready to walk single-file or even crawl in some places. Just a heads-up.
Okay. So, Felp opens the manhole cover and starts to climb down the ladder into the well. Despite his high dexterity, the ladder is slick with moss, algae, and water, as well as weak due to accumulated rust. He loses his foothold and slips, crashing into the water. Not only does he injure himself(-1 Hitpoint) his fall causes a lot of splashing around that is sure to alert any enemies around. Caleth follows behind Felp. The ladder is slippery, but he also has a pretty high Dexterity, and he manages not to fall. He clambers down the ladder quickly and without any problems. Honey Badger starts down the ladder next; it agilely slides down the ladder with ease. Trafire follows. She quickly and easily climbs down the ladder and reaches the bottom without a hitch. Jozan comes after Trafire. He loses his grip sometimes, and has some near misses, but he makes it to the bottom of the ladder successfully. Siber comes last. He starts down the ladder and nearly slips off; he loses both his handhold and his feethold, and slides down several rungs before managing to catch himself before he falls. Even though he does not fall, his near-miss causes a rather loud ringing sound from his hands and feet banging against the metal(although by now it's more rust and slime than metal) ladder. Jozan turns on his lantern.