There's no such thing as 100 men vs 1 gorilla, there's not enough space and it's logistically difficult to be effective with too many people. There's at best a rolling group of 10-12 men vs a gorilla and at least a few times over I expect the gorilla to be more than cable of incapacitating a group of men that size. It's just a matter of endurance which is where the gorilla falters vs humans, but even then they're likely stronger than multiple men while winded and worn out. Even worn out, if it fears for its life I doubt it'll be above simply reaching out and effortlessly crushing a few heads or necks like grapes. Even mindlessly flinging its arms around it'll knock some people out.
There's also the matter of whether any of the men can reach a threshold with their strength to commit any sort of cumulative damage that can be added to by successive men. I expect the bulk of the gorilla's surface area will barely be susceptible to the strike of even a strong human. This is an exaggeration but as an eg. if you throw one, ten, a hundred or a thousand rubber balls at a hard wall it doesn't matter, they don't reach the threshold required to exact any meaningful, cumulative damage. You'd have to bite, tear and scratch; and go for weak spots. I expect a gorilla woudn't be best pleased if you do any of this and will be inclined to prioritise your demise as a result. Once again surface area comes into play because few people could go for the vulnerable spots at once.
They're also smart, so they know what areas are important to try and protect. I also wouldn't confuse their tendency to be largely peaceful or to smartly retreat - with fear. If they see red, are pinned in and have to fight, their fear response if any is unlikely to be anywhere near as debilitating as ours can be, they're ultimately still wild animals and will go full ham if they have to. Other things to consider are things like testosterone. Their levels are 4-10x that of a man with high T and they're biologically more receptive to it too. They synthesise many times the muscle lounging around scratching their balls as the very best bodybuilders working out all year round.
Gorillas will have crazy levels of shock absorption, wide arm span, grip strength is about 4x a human, bite force is 8x, a full size prime gorilla is 4-20x stronger than a human male. Their muscle density is high and their twitch fibres are optimised for pure strength but they won't have to use a lot to effortlessly dispatch each person, so there may not be a lot of inroading of those fibres; another example of thresholds being important. You'd need like 20 perfectly coordinated people to dogpile it but I doubt it'd last and it'd break free, the weight would be too distributed and uneven.
They can break necks and crush organs in a single strike, crush skulls with their hands effortlessly and tear faces off with a single bite. A skull to a gorilla's hand is about the same as an orange to an elite climber, your neck? Even less..
The humans would have to wear it out on endurance then aggressively attack weak spots like the face/eyes and genitals; and I expect many of these people will be getting shredded, cracked and struck while they're doing it. Their head isn't that susceptible, you'd probably break your foot if you kicked their skull hard enough.
I think you'd need 100 insane, fearless, large, powerful and endurant men with excellent tactics and I think ~70 of them are dead, critically injured, paralysed or severely disabled for life by the time the gorilla is worn out enough to potentially be incapacitated -- faces hanging off, holes where their eyes used to be, necks crushed, legs arms now little more than broken twigs in a skin sheath. To kill it you'd literally have to tear into its neck with teeth and nails, then keep reaching in and digging till you hit a critical point. I think the killing comes after the incapacitation, not during the fight. I think you'd need legitimately animalistic people to go feral on it.
I think endurance is the first point and with it sacrifice, next is finding the few ways to deal cumulative damage as rapidly as possible. And again, thresholds: how many people can realistically attack at a time vs how many can the gorilla deal with at a time? Can an individual exact enough damage to contribute anything meaningful? How many people need to be left to still remain a threat?
The real question though should be 10-20 chimps vs 100 men..
