Yes it does and yes you can.
The reason some people are advising don't travel is because there is a very real risk it could be denied while you are out of the country, because you have missed the biometrics appointment. That is the law.
USCIS are notoriously bad with biometric rescheduling, and often if you miss an appointment they usually just deny, without sending another appointment. The onus is always on you, not them. They simply don't care - you are just a barcode to them.
Legally, you are ok to re-enter the US even if it is denied while out of the country, but that is legally speaking. USCIS don't always follow the law, and CBP make the odd howler from time to time too. People are erring on the side of caution here, for your sake.
Note that the guy you spoke to was talking rubbish. They can do it, he just didn't want to do it. They scan the barcode when you arrive, take the info, and done. Many of us here have done walk ins before or after the dates, it really doesn't matter. Try a different centre, or a day when that person isn't working perhaps.
Also, please stop referring to it as an interview - it isn't. It takes about a minute, is purely procedural, and your terminology can confuse it with an actual I-751 interview for people trying to help you.