CPU Utilization metrics not matching

The c5d.2xlarge instance type has 8 vCPUs. top will report CPU usage as a percentage of a single CPU. You can press I (shift + i, capital I) to toggle Irix mode, which is explained as:

    1. %CPU  --  CPU Usage
       The task's share of the elapsed CPU time since the last screen
       update, expressed as a percentage of total  CPU  time.   In  a
       true  SMP environment, if 'Irix mode' is Off, top will operate
       in 'Solaris mode' where a task's cpu usage will be divided  by
       the  total  number  of  CPUs.  You toggle 'Irix/Solaris' modes
       with the 'I' interactive command.

Otherwise, you can press 1 within top to show a break down of all the CPUs. This should give you data that is closer to what CloudWatch shows.