If that lazer was around, Han would not have said
"Blown away? How?"Luke...
" It would take a thousand ships with more firepower than I..."
So thats extreamly doubtfull.
As for the missing scene in EP3. I hope not. That scene had horrable acting my Mark and besides it occurs after Vader captured Leia. Thus it might be on the ANH DVD, but not in EP3 and not included in the actual storyline. Just as an extra like the Behind the Magic scenes are.
But of course anything can happen "Remember you only think you saw Han shoot first" I still have a problem with that scene. 🙁
Personaly i think it would be cool if they ended III right where IV begins, right c-3p0's first line, i figure they'll just skip like to ten years later and not have to deal with luke and leia's ageing all the way into his late teens or what ever, and show the plans being stolen and stuff. That would be cool. --> this thing is weird 🤣
I thought the Death Star's cold,unnatural presence stood out to Obi Wan, never really thought it was to do with his having seen one before.
As for adding footage from ANH onto Ep3, that'd be way too cheap. We all know GL has one hell of a lot to explain in 4 hours 20 minutes, we wouldn't want those last 20 minutes taken up by footage not good enough to make it to ANH originally.