Getting different results when changing the order of layers in __init__() function or adding an unused layer

If you want to reproduce the exact same results, it might be tricky to just seed the script, if you are using additional layers. Each additional layer will get a random parameter initialization, which calls to the pseudo-random number generator, and will thus most likely yield small differences.
Have a look at the Reproducibility doc and this thread for more information and let me know, if that doesn’t apply to your use case.