If an eyelet disintegrates, the spoke will pull through and lose tension. Which means the wheel will go way out of true. So yeah, it will pretty certainly fail sooner or later.

There's no reason to suspect that the failure will be catastrophic, but it may. I wouldn't ride it more than strictly necessary.

Rims don't normally split in half along the middle, but I've read about such an event as well on BF... not fun.