It has a hardware problem, possibly two, and you must fix it (come back) to repair it.
The two problems: flickering on the screen and problems with the touchpad / trackpad are most likely coincidental and have nothing to do with each other. Since he just received it on the screen and shows problems, he would have already recovered it.
The SMC reboot really has nothing to do with any of this. The SMC is just Apple's name for what the rest of the industry calls PMU or Energy Management Unit. When resetting it, the sensors, counters, guard dogs, etc. they return to "zero". The SMC simply regulates where the power goes and how fast to turn the fans based on the data it obtains from the rest of the system.
The fact that you have intermittent failed haptic feedback, a cursor that does not respond and a failure to connect to the keyboard / trackpad indicates that there is a hardware problem.
If it seems that the SMC reset "solves" your problem for a while but then returns, there is a good chance that there is a power problem as a defective component (resistor, capacitor, etc.), but in the end, the article should be repaired Most likely, you need a new upper case set.