The train approached on it's automated schedule. Psycho waited for validation.
As the second car passed, he saw exactly what he saw on that cargo sub just before the island froze. It was that container with the alien thing still trapped inside.
JSOC told Psycho to get on that train. There was no other option, as Psycho could not plant and detonate explosives at this point. Even if he did, there was no chance the explosives would destroy the crate or that thing inside. So, he ran as hard as he could.
Once in range, Psycho leaped forward using the power mode of the Nanosuit.
Just ahead a bluish light was about to meet Psycho's landing on the train.
Hopefully, he would survive!