I see nothing in that "extend a night on us" rate that suggests you will get lounge access or breakfast. Indeed, it appears to be 2/3rd's the rate of the non-club rooms.
I have been an ambassador for 5 years and have only gotten 'free' club benefits maybe once. They always try to upsell me anywhere from $35 to $100 per night. The ambassador status gets you a discounted club access upsell, it rarely gets you free club access.
This will not end as you hope. Another option is to call or email the hotel and ask how much the ambassador upsell is per night.