You can get self-generation of signals with circuitry of complexity as low as heart has. Few neurons needed.
What’s “latent sentience”? Where is the cutoff? Are ants sentient when they are so dumb they can follow their own feromone trail in circle until they die? Does this concern extend from carbon-based wetware to silicone-based systems too? If not, why?
Also, what about plants? They can sense their environment and react to it in fairly complex ways.
Mistakes will be made and are inevitable. There will be deaths of tissue cultures, lab animals, and perhaps even people (in any as complex environment as a laboratory building accidents happen; can range from ignition of alcohol vapors to attack by a crazy greenie to slipping on a staircase). But there are deaths on any option we do, including doing nothing.
Empty philosophy won’t do much. Lab work can achieve something.