"Roth IRA Certificate" appears to refer to a Certificate of Deposit in a Roth IRA.
The IRS cares only if the account is a Roth IRA or traditional IRA - they do not care about how you have your money invested within that Roth IRA.
So, unless the person saying "Roth IRA Certificate" tells you otherwise, this is the same as a Roth IRA; it's just a description of a particular type of investment vehicle within the IRA.