LP lose because of a troll player IN THE LOBBY!

Alright.. we love how riot is working to clear league community from toxic and trolls.. but that's just in the actual game. I was happy playing ranked and got matched into a lobby.. someone had mid role.. he was first pick then he instantly picked Adc and locked in then called he's Adc. Of course people will tell me.. "Then why didn't you talk with your team to change rolls and pick what's good for each other and smooth things over" and i will answer.. "I did but non listened because they were angry"... So instead of me losing 18 LP.. i had to dodge and lost 3 LP, That's not fair.. being forced to leave and lose LP even tho it's not your fault and having to wait since you dodged. If there is anything can be done to prevent this.. please let us know, a lot of people are forced to do as i did in order to prevent tragedy from happening and what they get in return.. a punishment for dodging.