Jenos can 1v1 weaker enemies very well, he can pump out some decent damage and then use his Void Grip to allow his teammates to gank you. If you are able to, try to continually shoulder peak him so that he can't Void Grip you, or take a teammate.
Hearing a Bomb King ult and no idea where he is coming from? 3 or more of you is on the point and can not escape? Keep your calm and fire your ult onto the ground, as he come out of his ult he's gonna be feared and there we go, your team is saved
Be ready for Jenos' ult. You have plenty of time to move out of the way as long as you are ready for the tell. Also, consider buying Resilience to shorten down the void grip if either they have it's legendary, or if you have no mobility.