It is important to note that you update the resource in your example.
If all meshes use that same resource, then it won’t work as you intended.
Instead, you can create a new buffer resource dynamically, and assign it:
local newBuff = buffer.create(...) -- as you do now
local resource_name = "/my_cloned_buffer.bufferc" -- make this unique for each resource!
local buffer_resource = reource.create_buffer(resource_name, { buffer = newBuff })
go.set(url, "vertices", buffer_resource) -- replace it's current resource hash, with the new one
Note, read the documentation! E.g. the name of the resource must be unique!
I.e. they can’t all be named /my_cloned_buffer.bufferc