There's many species of palms and it depends. Also in forest you could find extremely tall thin palms, I certainly wouldn't be loading them sideways.
Some plams dont have smooth trunks, some even have like 3" needles sticking out of them.
Some have small soft fronds you really wouldn't want to trust others have fronds 30' long you can grab no worries.
If you cant bigshot a line over the top then you dont have too many options left but to climb the trunk "somehow".
You can try to trunk walk with 2 flip lines and maybe a girth hitched rope to catch you if you slip. You'll likely find plenty of natives who'll scoot up there bare foot with a flip line. Apparently they make wine from the palms as well as palm oil..
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