IRL, a stubby dwarf soldier wearing 32 articles of clothing and full steel plate carrying a steel weapon and shield would have basically no chance ever of climbing up a rough cavern wall or up a tree.
Maybe they could climb a ladder but definitely not a rope, let alone a cliff face or something.
Ladder would fall and crush them, too fat.
I've seen really fat guys carrying heavy stuff climb up ladders... very slowly, but it's impossible. Admittedly, very sturdy ladders.
Don't you mean possible? Also, that has to be candy ladders using dwarven superglue or something xD
Yes, possible, I think my spell checker is retroactively correcting shit I typed to undermine me. A normal steel ladder welded to something extremely sturdy would do the trick, as I've observed IRL.
Dwarves live in fortresses and shit is made from stone and metal and their fortresses span vertically. Surely they'd have sturdy ladders for their fat, heavily armored soldiers to climb and that would be well within the scope of their core competencies.
Climbing anything else, I find highly unlikely for dwarves to do. Leave tree climbing and wall-scaling for thief-type invader characters and animals or monsters.