how to deal with proxy singed

Ok so just got promoted to b4. Jeez i know it sounds easy but it took me a fuckn week due to afks/trolls in my trials. Lol made it 3x and lost all 3 because of people leaving mid game for no reason. ANYWAYS. Just got promoted to B4. I main top but got jungle this game so i went panth. The other team has a proxy singed. I know how to deal with him in my own way. ( i buy good farming items and just try to match/out cs him and stop him from pushing towers. My top laner however this game had no idea how to deal with him. We lost due to 4 of my teamates chasing him when i would ping ping ping for them to stop. Any advice here? also, any more advice on how to deal with hardcore split pushers like yorick, tryn, yi? I just dont want to flop and get demoted because i honestly feel like im playing well. I know there is still A LOT MORE to learn including things i may be doing at the wrong time or not at all. I guess i really want to get better as well as play with better players. But if im 10/0/5, up in cs, smash my lane, ult other lanes ( as panth), push lanes that have waves, be in team fights, and still cant stop the relentless pushing, maybe my timing is off? like when i think i should ult in a team fight i should just push or visa versa?

ALSO in case you are wondering. I have been consistanlty working on my cs. Its kinda liek do i stay here and farm? or try and snowball. Most my wins with panth im like 15/3/5 with about 150-200 cs in a 20 min game. If they game goes past that i think my game managment needs help. I can record some of my losses and post them later. Maybe that will help. Any advice is greatly appreciated!!