There's no telling how long it'll run like that. If it's just a loose/worn out tensioner or a worn out belt it can potentially run like that for a long time but if it's a seizing bearing it can let go at any time. If yours sounds just like the car in the video it's most likely going to be the belt slipping against a pulley due to not enough tension, which points towards either a worn belt or a worn tensioner pulley.
If you have some silicone lubricant spray you can spray it on the belt while the engine is running and it will quiet the noise down temporarily but it won't fix the problem. Make sure it's silicone lube and not something like lithium grease. Using the silicone spray will also require that you clean all the pulleys when you get the problem fixed. You will still need to address the problem.
As to whether or not you can drive to work, I've been in that boat where you have to decide how long a repair can really wait so I know where you're coming from. In this case there are no guarantees. It might make it OK, it might strand you on the side of the road somewhere. If you decide to drive, keep the RPMs down as low as you can as a loose belt is more likely to give way with higher engine RPMs. When you do get this fixed I suggest replacing the belt, tensioner pulley and all idler pulleys (not sure how many an LS has).
