You need to use a remote load as a restraint, ensure the axial directionis free so the load can tension the rod, use a fixed hinge restraint at the other end.
Greetings, Bill is right you have to ensure the axial direction free
Try this first
Mesh your part before loading
Try to find natural frequency before loading
What is the OBE and SSE constrains for your model rectify that
the applicable Peak acceleration with respective to the amplitude must be 1.5 times 3.5g
apply these loads first as you are pulling from one end
What about the gravitational force I have gone through your model you have not defined them as gravitational force will act as restorting force.
Hopefully this will help you and let me know if it works
The remote load restraint is interesting. I suppose you use the Displacement (Rigid connection) for this and allow only axial movement. The difference with this solution compared to using the hole surface directly with the reference geometry fixture is the possibility to allow rotation, or are there more benefits with the remote load approach?