You guys aren't wrong. And honestly, the likelihood of it happening are slim to none, unless Burton filmed a secret cameo. I'm not holding my breath on that. Just a thought.
None of us knew that Seven was going to be in this, until she appeared in a trailer. I think it's very possible that Burton could film an appearance without us knowing. Doesn't mean I think he did, mind.
Personally, I'd be all for killing him in that attack. The idea of him losing his life due to androids/synth's feels very tragic, given his relationship with Data, and would add some weight to this show. It would be easier to do it offscreen, and given we haven't seen the character in 18 years, I don't think they should feel a need to explicitly show him dying, but I must be honest and say that offscreen deaths of big characters always just leave me feeling down. I can accept them doing it, it will just leave a bad taste, I think. And that's purely because I'm such a big fan of proper closure, I guess.