I think we are on firmer grounds defining sentience than consciousness. We already agree that non-humans can be sentient when we use the "ability to experience feelings and sensations" definition. Could we detect it in our AIs by how they react to stimulus, something like are they reacting as if they are aware they have an existence? Since we can detect sentience in non-humans, I can't see why we couldn't. Again, I doubt it will be anything like human or other biological sentience - we aren't going to build AIs to have the stimulus we get when our pain receptors are triggered, it would serve no purpose, and there isn't any analogue of that in a computer system. (And because of people with CIPA we know such a system is not necessary even for human sentience (they do however suffer from other problems that we describe as cognitive problems)). We also know human "internal" experience is different in different humans from simply asking each other about it.
Overall I can't see why we couldn't develop software that has sentience.