Tobias: You are right in the sense that one needs to go beyond mere “amoha” to have a tihetuka patisandhi. One needs to go to Abhidhamma to clarify this point.
I have not done a post on the eight types of kusala citta (I have done one on the 12 types of akusala citta in the Abhidhamma section).
In order to have a tihetuka patisandhi, one needs to do a kusala kamma with the first four types of kusala citta, which are “nanasampayutta” or “with knowledge”. Here with knowledge means “with the understanding that good kamma are bound to have good vipaka”.
This is discussed Bhikkhu Bodhi’s book “Comprehensive Manual of Abhidhamma” starting at p. 46.
– Similar explanation is likely to be in the pdf of Dr. Mehm Tin Mon.
Obviously, an understanding of Tilakkhana is not necessary here to be “nanasampayutta”.
– One first gets a tihetuka patisandhi by doing a kusala kamma with that “basic understanding”. Then once born with that tihetuka birth, one would be able to comprehend Tilakkhana.