Complex sentence: If the player quickly shoots her after eliminating Ourumov, she will yell to Trevelyan that she is wounded and to wait up for her; this buys the player more time to escape from the train.
Split into simpler sentences: If the player quickly shoots her after eliminating Ourumov, she will yell to Trevelyan that she is wounded and to wait up for her. This buys the player more time to escape from the train.