I used windsor on my last brew, i wanted to get us-04 for english IPA but they were sold out so i got windsor. I had lots of reservations after reading ppl opinions (low attenuation, low flock, someone described beer taste as pickled feet ect but i adjusted mashing temp (95min that started at 151 and ended at 147F). I pitched rehydrated yeast and got nice but nothing crazy, fermentation (64F wort and 64 ambient) that stopped after 40 hours, it was strange because from lots of bubbling in blow off tube went to nothing withing an hour or 2, i was sure it was low temp and i got stuck ferm so i checked SG and it was 1.014, and its still the same right now, 15 days later. So far it taste great, i was expecting FG at around 1.016-18 so i bumped IBU to 60 for this beer so it has nice malt/hop balance and im dryhoping now 2oz of mix hops.
So from my limited experience i think your beer is done and $6 for dry yeast is a rip-off, i was actually afraid of scenario like that so was considering adding different strain (us05 btw) to get it few points lower, im not sure its a good idea but if its really sweet i dont think carbonation will help much. BTW how do you know your us-05 batch is infected?, from the taste looks like your temp ferm was out of range, i would give them 2 more weeks in primary at 70 and then decide what to do