I just put that as possibility there as I read an article on Jalopnik.
What could be controlled with an hacked ECU ?
ABS-ESP : you could break a wheel down which acts as steering in a very harsh way. The break circuit itself no.
E-Accelerator : yes . Wired accel. no.
Steering : While companies like Nissan (Juke) have steering by wire, the also have a tradition steering column as backup. So for car noadays no. In the future with only drive by wire, yes.
This is all very theoretical, but it can be done. You still need to lay hands on the car first though.
The question like asked in the US congress : Could some kid from India hack your car? , is still no for me. But a tinkered ECU, yes.
As for this case or any other case of wierd coincidence, we will, might never know.
I just think with what they do and did in the past, official, un official but proven, it can be. I surely don't trust them or would you bet your life on them?