Collision horizontal and vertical rods- Rotational mechanics How to use coefficient of restitution.
Channel: Z13 Physics Y Kumar
Date: 2020-12-17

This can be solved if you take angular momentum about impact point. 
But pl see, if one can solve problem by two methods it does not mean that one of them is incorrect necessarily.

Also please note, the point which we take for conservation of Angular momentum is Not fixed to body( which some people think) but is fixed to fixed reference frame. And it is at a given instant. At that moment it coincided with com.