That latch just pulls a cable that releases a catch like a hood release. It's crude and prone to misalignment. Look in there with a flashlight as you pull on the latch and see if the cable is pulling or loose and if you can reach in enough to pull the cable or the catch. Sometimes the release you are to push doesn't have enough room to pull the cable far enough to release the latch.
Your coach has one large foot rest - mine has two and both of mine are balky and noisy on the road and pretty much a bad idea. And the joke of a "bed" they make is even worse.
2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad