I am working on a way to make random tests without a reference solution but Im not sure if I will manage to make them perfectly reliable, so for now I used your solution as a reference solution as it was the fastest of all of the submitted solutions so far.
Thank you very much for the advice, please let me know if there is anything else I should change :)

You can try yourself. If you take another solution, it's fine too; just make sure to add a comment in the code with credit to original author.

As I havn't made a kata before, I'm not sure what would be acceptable or not. Should I try to make a better performing solution myself or would it be acceptable to take a solution submitted by somebody else as a reference solution?

Since your tests are performance-heavy, I suggest you use a faster reference solution.

I misspelt the method name, idk how I didnt realise. Thanks

sample tests have wrong function name

findConsequtiveSubstringsIn should be findConsecutiveSubstringsIn

Thanks, I noticed that mistake in the example tests but forgot to fix it in the description.

"abcccabab"       3

Why is the expected result 3?

If the index is zero-based, then 3 would be the second 'c' instead of the first 'c'.

Clarifying that ' alone does not count as a word would be nice.
Overall, it was a fun and interesting kata.