The way I would do it without seeing the implementation:

- Atomic to track print order (name it counter).

- Results slice stores items: {index, err, data}.

- Goroutines: do work, store result, then loop-check if counter matches index to print (with tiny sleep).

Edit: Another solution would be to put printing loop outside with a channel to signal work finished but I don't know how I would avoid using nested loops, one for the items in the list and one to check if the result is back.