Yea, trying to use 3 weekend certs together, a Fri-Sat-Sun night combo is your only option.
As to DPs on using these at Waldorf's, not sure what exactly you're looking for, as long as there is the basic/standard points redemption room available then you can use these certificates (assuming of course it is a Fri/Sat/Sun night and not at one of the few excluded properties mentioned above). If you narrow down your search a little then I would take a look at the dedicated threads here for the property to see what award availability looks like.