End Time 0.001095 s
Result Number of Points 5000
To resolve a 100 Hz vibration, you need 0.01 seconds to get one cycle, but the end time is only a tenth of a cycle. I recommend a longer End Time to catch any ringing at 100 Hz.
To resolve a 5000 Hz cycle, you need 20 points per cycle, which is a sampling rate of 100,000 Hz or a time step of 1e-5 s. The Explicit solver is taking much smaller time steps, and you have requested 5000 points in .001095 s, so the sampling rate is met for the current end time. However, if you increase the End time, you will reduce the sample rate since you have specified a Result Number of points. Recheck the sample rate if you change the end time.
The solver maximum time step is calculated based on the smallest characteristic length of all the elements. You can make an Element Quality plot of Characteristic length to see which element is defining the maximum solver time step. If you can make that element characteristic length twice as large, the maximum solver time step can be twice as large which will reduce the wait time for the solution.