How will stake react if users are playing from a restricted area and submit ID from that restricted region?
Will they get banned or restricted immediately?
Stake is still a business like any other business out there, and it's very important to respect their terms of service to avoid loses and any potential embarrassment that may follow suit as a result.
The casino made known their list of countries that are restricted from using their casino for a reason, and there is also a warning when you are visiting the site from a restricted country without the use of VPN, all this should tell you that there is a heavy punishment for you if you ignore all of this and still go ahead to play from a restricted place.
Your account Wil not only be banned, but also, the funds on that account will be confiscated as well.