Remembering always that all I can say is what I think makes the most sense from the material I have read, here is my view:
To summarize in my own words. EP states we can reach conclusions about gods through the anticipations. Gods are blissful and are not immortal per se, but have reached a level of competence which enable them to stop their body from 'falling apart' and die (so to speak).
Yes, that is pretty much exactly correct per my reading. What I would add is that the "conclusions" that can be reached about the gods through anticipations are probably pretty limited, to the view that such beings exist, and that since the goal of all life is total pleasure (with zero pain or as little as possible) then beings which have reached the zenith are leading lives that are fully pleasurable to them and are not concerned with rewarding human friends or punishing human enemies. In other words the conclusions that we can be confident about are pretty high level and the more detailed speculation you get into about how they spend their time, beyond the basics, the less confidence we can have in that particular speculation, such as "the gods speak Greek" or look like humans,
As simulacra in dreams about gods are insufficient proof of their existence and/or their properties we cannot infer that by simulacra in dreams about dead people, dead people have exist or have the same properties.
Now that one I think is mostly correct in both parts of the sentence but your are linking them in way that might need to be unwound. Yes I would say that Epicurus would hold that images of gods received in dreams is not sufficient proof of their existence. Yes I would say that Epicurus would hold that images of dead people (or anything else) received in a dream are not sufficient proof of the reality of what has been dreamed. Now whether the images received in dreams of gods vs dreams of people have any relationship that might need further discussion, because I get the impression that dreams of dead people and other things are generally dreams involving things that we have actually seen in the past, while awake, in distinction to dreams about gods, which pretty much by definition we have never seen while awake. So there is probably a distinction worth thinking about there.