After lock will activate you can just go back to the tunnel a little bit and then you need to back to the place where lock is. The thing is, when you go back into the tunnel, area with lock will unload, and because of that lock will not work, so you will be able to press the button and use cable car. Second way is a little bit more complicated. We are using for it flybash. Flybash is an abbility which makes you fly in the air after bouncing from formation/tent and pressing "punch/action" button. When your combo bar will be full, just punch one roman, only one time, and even after your combo bar will run out, you will be able to make flybash. Remember that when you punch another roman, this ability will run out. You can gain this ability, before making helvetia tardis. You can just full your combo bar on the catapult which is located before the bridge and then just punch one roman on the bridge. After that you need to talk with sam and go back to the bridge where we are using tardis (You can look on
#recent-strats, there is guide made by Failentin, which will tell you what you need to do to perform this tardis). After performed tardis you are going to the sector with lock and you need to bounce off from one formation, and make flybash to the rock shelf on which located is a button that opens the door to the next sector and a lever that gives you a magic potion. The line in the picture shows where you should be in order to be able to jump on this rock ledge. Also remember to bounce off as high as possible and then press the "punch/action" button as fast as you can.