this is an impossible scenario in 5v5, and if it is, then that's just your teams' mistake that you get punished for.
There's 0 emphasis on anything other than objectives. Some of the maps are just completely ass when it comes to this and the objectives have way too much of an impact on the rest of the game. You can wipe a team 3 times in a row, like right after they respawn, and still end up behind in XP (like seriously shared xp...wow) because the other team's fifth person decides to go do a bruiser camp. Regardless of the fact that I've played 0 games of serious 5v5 matches the game is as shallow as mobas come, and I thought League had a small ceiling.
as i said, solo queueing it DOES suck. but that's why there's literally NO RATED SOLO QUEUE in this game at all. this is very different to how lol and dota are made where 99.9% of the playerbase knows the games only via solo queue.
there's a hero league with ratings and ranks, but it doesn't matter - you can queue with a team of any size. it will just try to match you vs an equal team with an equal setup of parties in it. nobody will care about hero league rank at all - it's not going to be the same thing as being d1 or 5k mmr in dota or whatever.
the main competitive format with rewards will be 5v5 teams. that's the way they want you to play it - you will have a little group of friends/clan/community and you will just queue as mixes or with the same team all the time (depending on how competitive you want to be). sort of like when wow had charters, you know? or when dota allstars was actually good before the solo queue leagues were created and we played clan inhouse games or friendlist chain games only? this is exactly what they want to bring back, just on a larger scale.