The snarky answer is: you already know:
“…ask friends, colleagues, and other content creators what they normally charge for licensing? Would you base it off your previous experience creating commercial-like content? Like what would a similar video cost to produce, or how much would you be willing to pay based on what you know about advertising budgets….”
Benchmarking is what you call it when you look around to see what others charge for a similar product. You’ll want to do that research checking sources like Getty, Adobe stock ,etc.
You don’t say how unique your clip is. If it is truly one of a kind, you can ask anything you like, within reason. If not unique, then yes the next question becomes how much would it cost to replicate it, then aim for maybe …20 percent…? less than that.
Another way to go would be to not worry about maximizing the profit, as if this was some kind of blood sport contest, and just picking a number that represents the value of the time and trouble and money you initially spent to get the shot, then adding some reasonable markup to that. Those numbers, you probably do have a good grasp of. But also consider that if the usage is exclusive, you won’t be making any more off of it, until the exclusionary period is over. If you think you’ll be able to re-sell this shot over and over in a stock footage library service, you’d want to charge a little less and make it up on overall volume. If this one usage is going to basically “burn up” the demand for the shot in the long term, so you won’t get many more sales out of it after the campaign, you can raise the price a bit more.
So I didn’t really give you a hard number; I gave you principles that could lead to computing the number, based on what you yourself want to do and how you value the product.
Some viral campaigns might come and go and lose control of the stock footage they used, only to find after some time that parody-makers now can get the same shot and use it to make their parodies more effective. Not likely, but also a non-zero chance. I suppose.