@jacob.small thanks for clarifying that, I meant to post that revision after beating my head on the desk and searching google for what the error was in 2.x!
Order doesn’t matter, but you need to make sure the index aligns to what you are expecting to pass, so in the lower option the index would be 0 not 1.
Also if you want to wait for many things gather all of the many into one list or make multiple ‘WaitFor’ entries - something like this [passthrough, a,b,c,d,e,f][0]; will result in passing the data into the passthrough node after the data for passthrough, a, b, c, d, e, and f are all received.