https://www.getguesstimate.com/models/18631
It’s rudimentary but demonstrates quantitatively how probabilities favoring one origin scenario or another can be reached. Easy to copy-paste it so any set of priors can be applied and collectively estimated,
More rigorous treatment can be found at https://www.researchgate.net/publication/345753939_Outlines_...
There are other similar types of analyses out there if you google around.