what the heck is causing this melting near wireless charging pad??

Um, heat? Does the car sit in the direct sun? Those symbols in yellow are Caution, Hot Surface and Read the manual. And the other pic says "Don't put the phone on top of coins, keys or paper clips in the tray"

In my experience, wireless charging pads are only good for heating up your phone, not charging it. Can't you just use a USB charging cable?

 

Good catch ! That's gotta hurt, hell it hurts just lookin at it.
Does it charge as fast on that pad as it charges using the charger that came with the phone (if you got one with the phone). How often is(are) the phone(s) on that pad?

 

Definitely, during that honeymoon period between unboxing a phone and the USB-C port becoming unusable....