I just found out that the people onboard the Titan submarine are dead. Is OceanGate in trouble?

Not only is the CEO dead, I think that people are going to be a lot more hesitant going on anything the company makes from now on. That's not even mentioning the possibility of them being sued.

A lot of people mention the waiver, which...sure, there's some assumption of the risk for diving to the bottom of the ocean. But a waiver won't exclude you from gross incompetence and negligence.

If I ran an indoor trampoline park, I may have you sign a waiver before you can use it. This makes sense, as jumping on trampolines carries with it some inherit risk of physical injury. That's a risk you have to acknowledge before you can come in. However, if you got injured because the building caught on fire, and due to my negligence I've blocked all the fire exits with flammable material, that's a bit beyond the assumption of risk covered by the waiver. I would totally be liable for any damages that result.

Did the Titan implode due to the inherit risk of deep sea exploration? Or did it implode due to a dereliction of safety precautions? (It's that one)

The CEO is definitely going down for this.

Probably. They got people to sign a waiver so they're probably partially covered, but there will no doubt be some law suits occuring and a lot of money going from both sides to pay for them.

I'm thinking the company is done for.

IANAL, but I imagine that being in the middle of the ocean would provide some immunity because the "crime" was jurisdictionless.