Is this grammatically correct? What does it mean and can it be rephrased? You need to understand that if he knows, he can’t gatekeep it. He clearly hasn’t gotten a feedback as to when we would do our defense. So chill, if he has the information, he would

Yes, the sentence is grammatically correct. Here's a breakdown of its meaning: The speaker is advising someone to understand that if "he" (likely referring to a specific person) knows certain information, he cannot keep it to himself or hide it (i.e., "gatekeep it"). The speaker also points out that this person has not received any feedback about when they would have their defense (likely a thesis or project presentation). Therefore, the speaker is suggesting to relax because if he has the necessary information, he will eventually share it with them. Here’s a rephrased version: "You need to realize that if he knows the information, he can't keep it from us. It seems he hasn't received any updates on when our defense will take place. So relax; if he does have the information, he will let us know."