Isn't After landing C/L in A320 challenge-n-response?

[Sidestick_n_Rudder]

I suggest that the OP answers himself these two questions:

1) What can happen if PM accidentally skips a point in "After LDG" checklist, because he reads it himself with no monitoring from PF?

2) What can happen if PM accidentally taxies into the grass (or perhaps onto an active runway), while he is distracted by cross-checking the after-landing items of the PM