You have a couple options, but I think they would all involve using an IF statement.

Explain how you have their availability schedule in Excel.

Correct me if I'm wrong, but you are attempting to consolidate your workers' availability for the week?

This may seem complicated, but it's not that bad. There may even be an easier way to do it. This is what comes to mind...

Let's say you note an employee's availability by Y or N under the day they are or are not available. You create two cells, off to the side somewhere. One is Y and one is N, or whatever you actually use to make distinguish the worker's availability.

If available on Monday, make a note in cell B2, if not make a different note in cell B2. If available on Tuesday, make a note in cell C2, if not make a different not in cell C2... This is why you created the two cells: Y and N.
So, if Bob is available on Monday, then we see that in cell B2, there's a Y. I placed my Y and N cells off at B 100 and B101. So, IF(B2=B100,'Worker Availability Sheet'! B2= Yes, No). Something like that.

You write the statement once, lock in your source data (using $ sign in front of the column or row, depending on what you need to lock), then drag it out for the week. Then copy it for each worker.

Good luck