Initially, I had similar thoughts with regards to Annabeth having lost a lot of blood, it shouldn't be this easy to just revive her without putting all that blood back inside her. But then I thought, hey, this is a show about people with superpowers, gotta suspend your disbelief a little I suppose.
By the way, I have a theory about Cipher. First of all, I think it's pretty heavily implied, that the guy in his hyperbaric chamber is Thomas Godolkin, due to him being heavily burned, and if you remember the first scene of the season, he was in that lab for project Odessa when it went up in flames. There would have been a lot of fumes of Compound V in the air, which is how I think he survived this long, and also got superpowers. The theory is that he is the one actually puppeteering people, not Cipher. Cipher is perhaps actually just another puppet of his. Sister Sage seems to be aware of this, which is implied by the look she gave him when she was having sex with Cipher. That would explain why Jordan felt he was "always in pain" - because of the burn wounds.
So, perhaps Cipher really is just a regular human with no V in his blood. If he is Godolkin's son, like he claims, then perhaps he was born before the accident in the lab. It doesn't explain however why he looked exactly the same age when Marie was born. There are still plenty of mysteries left unsolved I suppose. Can't wait for the next episode.