Lucidstuck I

If this plan does not go smoothly, it will be obvious that the Observers are involved, since it is too complex for someone without near-omniscience to accomplish and Daydream doesn't quite have the ability to interact that we do. If something tips off Lucia that Alice was involved - perhaps, after the mission is over, and someone mentions it? Or even Alice herself showing back up and mentioning it because she can be a little vindictive and bitchy that way? Then having had it happen behind her back without a chance to come to terms with the idea that it was happening can easily make Lucia more suspicious of our commands or even invoke her ire in our direction.

I stand by the 2. option as it is, with the hopes that we're allowed to guide conversation upon arrival.
That said I do not oppose the Discord order-chain, just pointing out a larger unknown factor and more points where it can all come tumbling down. I advise caution, as always.

They're already dealing with a boss and are going to have to handle the Alice/Lucia drama. I think they'll be a little preoccupied with that to wonder if semi-omniscient beings are orchestrating some plan for unknown reasons. Even if Alice tries bringing it up why would Lucia listen to her? She hates her and has every reason to assume she's just trying to mess with her.

Besides, it's not like we're doing anything bad by doing this. We're just making sure theres no drama that comes up while we take care of a large, potentially dangerous creature that's capable of a TPK.