I'm new in aviation. I think they have done a good job.
But why didn't they return to the airport?
According to the chart above it looks to me that a return
to the airport wasn't longer than the flight they have done.
They
WERE trying to return to the airport or maybe another airport. Probably with vectors from ATC. They also probably expected to keep flying with at least one engine producing power.
As was said before, the bird ingestion probably happened early in the flight and they continued to climb while they sorted things out. I expect the damage was to both engines and they did not continue running well enough to make it all the way back.