I’d be inclined to do the 20-min test protocol. FTP is about training levels below FTP, so your results on Dade +4 aren’t relevant. Your Zwift TT can provide better guidance but make sure you are looking at average power (not normalized).
Ramp tests are designed to test maximum aerobic capacity. And like any protocol they have errors when used to estimate FTP.
Since you do TTs and should know how to pace efforts, its better in my opinion to stick with the traditional 20-minute protocol that is available in TrainerRoad’s library.