Ethan is probably infected but they say in the files that it takes significant exposure to Eveline to be irreversibly infected. Lucas managed to get the mold removed via brain surgery, Ethan can probably do something similar (if he even needs it, he was only there for <12 hours).
My personal theory is that the serum is a dud. Good for killing infected but Mia and Zoe were too far gone at this point to be "cured" like that, considering that Zoe dies and Mia gets immediately reinfected no matter what. Killing Eveline is the only way to render the mold truly dormant.
Seems that way. They were in contact with Lucas and apparently were the ones who paid for/performed for his brain surgery to remove the mold. They were probably using the Bakers as a test run for Eveline. My theory is that they are likely the same company who Mia worked for, who came to investigate the shipwreck and recover Eveline but are taking advantage of the situation to get some of that ever nebulous "combat data".
Yeah, Lucas wasn't under Eveline's control at all. He was just that crazy normally. As for how he can regenerate, it's a little unclear if only infected can do that or it normal people also can with the health drinks (the description is a little unclear). Ethan can't regenerate like Jack but he can reattach limbs so idk.
Seems that way! Provided that is actually Umbrella. And that is actually Chris. x-filestheme.mp3
Seems to be a bit of both. Sufficiently infected people will become Molded (like Jack did) but Eveline seems to be able to create her own mold/biomass via vomiting (natch) which she can also use to create Molded.