Yea, don't exercise the 5th year tender. It's fully guaranteed the moment it's exercised.
Previous years it was only fully guaranteed for injury up until the 5th year started.*
*Example is Blake Bortles was injured and couldn't pass a physical going into the start of the 5th year, therefore his 5th year option was fully guaranteed. That's why the Jags extended him so they could drop the cap cause his 5th year option was too expensive. And of course that blew up on them the following year but they had to extend him due to the cap hit he was going to have for that year.