That video is basically the best possible outcome given a number of variables that are completely out of your control.
Here is how I narrated that video in my head:
I go buff to buff hoping for the early level 3 gank bot lane, taking gromp instead of wolves so I enter the lane I'm ganking with lower health than I had to so I could hide my wolves by showing the enemy jungler gromp is gone and hoping he assumes I cleared that side of the jungle and/or doesn't want to go that deep for wolf camp.
I go to take scuttle after my bot lane decides to do the exact opposite of what we had discussed during which time the enemy Brand chases braum into what I can only assume is a completely unwarded river given how far up both jhin and brand had walked afterward. I punish this stupidity and pick up a kill. Thank god for idiots.
Then I go back to take my wolf camp and think to myself "hey if brand was dumb enough to chase braum into an unwarded river without knowledge of where I'm at, I bet he's dumb enough to over extend the second he comes back to lane despite the fact that he just flashed (because in reality there is no universe where Veigar hasn't taken his stun by level 4 and a simple glance at my minimap tells me that veigar is playing passively and not over extending probably because he knows his jungler picked a champion that is useless for the first 20 minutes of the game and losing lane early means he's screwed).
I make my way toward bot through the river from mid looking at my mini map and marveling over the fact that none of the enemy players are reacting to the fact that I just walked by 3 of the most common places for people to place wards (guess no one is warding at all on that enemy team) and proceed to bot lane as they get greedy and extend past mid lane without vision to try to pick up a kill on braum. I again punish the blatantly ridiculous decision, thank whatever deity decided to bless me with such an intense bout of luck, and recall.
Now I have no camps bot to farm so I recall and head top praying that I have camps left after ganking bot twice in a row which should have screamed to master Yi "Take this dude's krugs and wraiths." Fortunately this master Yi is bad (not to mention he's playing master yi) and I quickly discover that my krugs are still there. I consider ganking for Shen but, just like all laners, he must have not looked at the minimap and taken note that I was going to be topside within 45 seconds of killing brand again. Because of this lack of insight, he allows himself to take enough damage to make ganking too high risk. So I go back to my krugs that Master Yi has so graciously gifted me. Thanks, Yi!
But whats this?! A wild Yi has appeared! He must be on his wave to dive Shen at the turret with fiora (because his meditate is ridiculous but given its on such a binary useless champion, we let him get away with it).
Yi walks under turret despite the fact that fiora won't be able to safely push her minions under the turret but gets lucky when one just barely walks into turret range to take the first turret hit for him. His luck ends there however as fiora isn't in position to take advantage of the Yi's dive and gets minion blocked when she starts moving. At this point I channel my ESP abilities to surmise the thoughts of this Fiora. There were as follows:
"Please tell me this Yi isn't about to do what I think he's going to do. There is no way for me to get these minions under turret fast enough to allow him to alpha to save himself after he pops mediate. Well fuck it at least when he dies I'll pick up the kill. I'm cool with that. I'm playing Fiora and she's busted. Onward...fuck, get out of my way minion..MOOOOVE you piece of shit. God, Rito needs to do something about minion block."
At this moment the stars align. And by stars aligning I mean Yi enters shen's taunt range AT THE EXACT SAME MOMENT he sees me. Ty Allah/God/Zeus/spaghetti monster for your copious gifts on this day. I shall spread word of your glory through my youtube channel (but don't read the comments. People are monsters and you should definitely get back into the habit of smiting assholes.) Shen lands his taunt and takes zero damage from yi as he dodges all the damage put out by this autoattack champion who decided to dive him (a shen). Shen's shield doesn't even get removed as Yi goes on full retreat and wastes his flash as the finishing turret shot was already in the air, and dies as he watches Fiora still struggling with the minion body block. Another kill. Count it. THE END. <Applause>
Now I'm not saying you did a bad job or am judging any of the what you did ( really just wanted to make a fun narrative for that video), I'm just saying that this really was a HUGE display of luck/enemy idiocy and not so much a show of decision making. The real take away here is "Punish spent flashes, poor enemy vision, over extended laners, and people who decide to dive champions that excel at turning dives."
Anyway, hope you got a laugh out of it.