Plat 2 jungler incredibly frustrated and in need of help

So I'll point out that I have grinded a few accounts to plat2 around same winrate and peaked at d4. usually 65 (for some reason my best jungler kayn pooped the bed on this acc...) and I can't understand why I don't carry/win more often with him this time around but i digress...

I struggle with tilting. A huge tilting issue with me is when i ping 20x for a gank, the lane doesn't follow and I die when it should have been a free kill or i waste my time/at best trade 1 for 1 in a 2v1. Another common tilting problem is when I ward and tell people "jungle is here please play safe or ward" and they die anyway. Sometimes those games devolve into rage fests with entire team flaming and I come to find out the guy who died to the jungler 10x whos location was known had everyone muted since start.... so there was no chance of me informing him even.

My second struggle is picks. My blue kayn is by far my best pick but I can't draft him in 90 percent of the team comps I feel because they A - Lack a tank all together or B - the tank doesn't know when/how to start a fight which forces my hand. This is also the cast with ALL ad teams which is REALLY common now with yas buffs... yas mid anyone....

My final struggle is all the things I don't know but should be doing. I'm unsure how to solve that issue. As a jungle im VERY good at tracking enemy jungle. If i can't win a fight or cannot show to the fight i almost always tell them where he is and if i can't be there. I am a great teamfighter from my other gaming backround mechanics are my best attribute but clearly i'm missing something.

I'll add that when i duo with my buddy my winrates 80 percent+. We are both d4 at our highest and i'm positive we can get higher but I need to know why SOLO i'm struggling so much...