Opening a second savings account with an existing SDFCU account

This question if for Americans who have a State Department Federal Credit Union account.

Many expats do because they accept a foreign address even to open an account.

As you know when you first open the account you need to be a member of one of the organizations on their list and then you get an investment account and also a savings account. As it's a credit union mostly for State Department employees but they offer other ways in if you're not.

After that, I don't think they everr check if you're still a menber of that organization.

So here's the rub.

For THAI tax purposes I want a second savings account with them.

I'm pretty sure they can do that but I'm posting here to ask if anyone has tried that and if they require to prove membership in one of the organizations on their list to open a second account for existing customs.

Yes I' realize I could just ask them but I'd rather know in advance for obvious reasons.