Scam. If anyone asks you for $3k over the phone without even finalising the interview and international police check it’s not legitimate. The guy also got really pushy when I started to tell him to call back tomorrow I want to do my research before progressing with the payment which was a huge red flag. Like of course they can call you back! Also there is no online portal it’s all via email which is suss. Go through the official United States website only. None of the consultants can be found on LinkedIn etc either or are likely to be able to send you and application confirmation number for the USA gov website.