No players dont make 2 salaries. Heres how it works with amnestied players
Elton Brand got amnestied for his 18.1 mil salary for the upcoming season by the 76ers. He entered the 48 hour waiver period where teams under the cap can bid and the highest bidder gets the player and pays their portion under the cap. The Mavs won at 2.1 mil. That means the Mavs pay that portion(2.1) and the Sixers pay the rest(16 mil) but doesnt count against the cap.
Brandon Roy got amnestied and cleared the 48 hour waiver period without getting bid on. That means the Blazers have to pay him the remaining salary on his contract while it doesnt count against the cap. Hes due 16.3 mil from Portland but could sign with any team for the vet minimum to bolster a roster and if the T Wolves sign him for the 1.4 vet minimum then the Wolves pay 1.4 and the Blazers pay 14.9 mil relieving them of some of the salary on the contract. Signing him at say the MLE of 5 million would do nothing but help the former team and does nothing for the player while hurting his current team.
so all the amnestied players are pretty much playing for their new teams for free