Laid off, former employer bought by new company with their own insurance plan, am I still COBRA eligible?

I’m in PA.

Laid off July 11th. Unbeknownst to me, my company was in negotiations to be “absorbed” into a larger company. The merge is now complete. The new company has insurance with a different company and that is what everyone is being moved to.

I reached out to my former HR manager and she said since our plan with Aetna is no longer in force, I am not eligible to enroll in COBRA.

First, it’s a month later and this is the first I heard. It would have been nice if they had let me know of this so I could have started looking for alternatives. In the back of my mind I was under the impression I had a 60 day window in case of an emergency. That apparently wasn’t the case. Hopefully I can get through August unscathed.

Secondly, is this even accurate? The bigger company that bought us has health insurance. Wouldn’t I be able to enroll in their plan via COBRA since they basically took over? All the former employees of my company have been transitioned to it already. Am I just SOL here?