Well yes, but you could just as easily prove that canon!Asuka could secretly be a practicing Satanist, or a Skrull impersonator, or the anonymous author of a best-selling series of romance novels. If your only criteria is "this isn't actually proven untrue by canonical information and you can interpret some of her behaviour as being related to it", the sky's the limit.
... Except that all of those scenarios you've described are far from easy to tie into anything that we've seen of Asuka.
I mean, seriously, a practicing
Satanist? She had ample opportunity to proclaim such beliefs the few times the topic of the Angels' nature came up between her and Shinji; and why would a practicing Satanist cite the Walls of Jericho, which is part of the Bible? (Not saying that someone can't write a Satanist Asuka; just that they have to admit that canon!Asuka, in spite of the room for alternative interpretation, is so unlikely to the point of practical impossibility to be a Satanist without
something happening that led to her converting to the religion.)
An anonymous best-selling author? That is irreconciliable with her prideful glory-seeking personality, at the very least!
And for the record, IINM you wouldn't be able to tell if someone was a Skrull impersonator unless they did a poor job of researching the individual they're impersonating or they get physically injured in such a way that reveals their true alien anatomy. So
anyone in the EVA cast could be a Skrull impersonator! (Well, except Kaji, because it's implied they recovered his corpse and nobody noted anything unusual about it; and then everyone who got tanged in EOE must have been human, else why would GNR/Lilith bother tanging them in the first place?)
"Asuka what are you doing with that pentagram?"
"I'm practising my religion you jackass"
"What sort of religion involves a pentagram?"
"Satanism"
"You're a Satanist?"
"Well we kill angels. So I kind of figure God' be pissed about that"
"...I concede to your logic"
"Good, now help me with the goat"
"Yes Asuka"
"Now say it with me Shinji"
"HAIL SATAN"
"HAIL SATAN"
"I feel dirty"
"Silly Shinji, that's how you know it works"
:lol Now I want to see a fic about this!