I think the Pattern is growing chaotic under stress of the Dark One to such an extent that rather than being subtly guided, individuals caught up in Rand's t'a'veren web are being forced into situations where they quickly fulfill their purposes.

I really think Verin had other things to accomplish before going to the Tower, and did not count on getting ensnared in yet another t'a'veren tangle via Mat, so was unable to fulfill her complete goals the way she had liked to.