A testcase could be n = 4000, m = 4000, which will evaluate to -96 in i16

You should have the factors in the first array, and the number of each in the second
So one 2 and one 5 are written as an array containin the 2 and 5, and a second array containing the number of them; one of each
so it's [[2,5],[1,1]]

For some reason the random tests require the anser to be -1. As you can see, I was forced to either wait for the bug to be fixed, forfeit this kata or cheat the bug.

Same here:
Wrong result for recipe
{'butter': 73, 'crumbles': 54, 'chocolate': 91}
and available ingredients
{'butter': 9326, 'crumbles': 3929, 'chocolate': 1394} #unrequired ingredients removed te declutter
: 15 should equal -1

Clever! How you use binary mapping of the three cells to make a single condition check.

You could have used a defaultdict instead of the getPriority function.

I said it should NOT result in PASSWORDPASSWORDPASSWORD. This is one of the default test cases, but I can't see how that testcase could be right.

A missing first or last element is not a sequence with a single element missing.
[2,3,4,5,6] is a correct sequence, it is not correct to state it should be [1,2,3,4,5,6] or [2,3,4,5,6,7]