fwiw, i also looked at NZ, BR, UA, TK, and AC's earning charts for AI, and it is all over the place:

- A class is suites/first on KF, but prem econ on others. BR does show A class as first before Jun 23
- L, U, T, S fare classes isnt listed on KF and NZ, but they do earn on other. NZ's website do state that "Booking classes that are not mentioned are not eligible for accrual."

the following are what is most relevant to you:

- TK specifically says "Booking classes not eligible for accrual: O, I, X, R, N, A", but they do earn on a few others. R, A, N are also prem econ fare class, so if they dont earn on TK, then it is possible for E class not to earn with KF. for completeness, these 3 fare class are also not listed on KF's chart
-- E class is not also listed in any of these charts except UA's. as stated above, NZ do mentioned that you cant earn if the fare class isnt listed, and i expect similar terms to be listed somewhere for other airlines

imo, i think the problem is with AI than the other airlines given how misaligned the charts are. and i think you made the right decision to move on