Can I be discharged for a pre existing condition even though I disclosed that information to my recruiter?

You disclosed it to your Recruiter but failed to mention this as MEPS.....you withheld medically important information and signed the document stating that the information you provided is true? This is fraudulent enlistment. You purposefully lied and broke the law. You should be lucky that getting discharged with no benefits is the only thing that happened to you.

It doesn't matter if your recruiter knew.
On block 15a of the DD 2807, where you were asked "HAVE YOU EVER HAD OR DO YOU NOW HAVE: Seizures, convulsions, epilepsy or fits?"
You lied on this question and signed the form.
And the very top of that form warns you that lying on this can result in fines and jail time.
That is a Fraudulent Enlistment and violation of ART 83, UCMJ resulting in up to a Dishonorable Discharge and up to two years confinement.
Yes, they are "allowed to do that".
If you get an RE 4, there is nothing to fight.
If you get an RE 3, there is a chance you can get a waiver to get back in, but now you have to answer yes to the epilepsy question AND 26."Have you ever been discharged from military service for any reason?"

If I get this story right, the recruiter told you to lie on your resume/disclosure. You then knowingly, or should have known, lied. The recruiter misled you. That mistake doesn't mitigate medical. If you were let go simply due to medical, count your blessings as a worse Separation Code could have been applied that would be an albatross hanging on your neck following you around in the CIV world. You must know recruiters can't make medical diagnosis/prognosis, risk decisions. Take it as a learning experience about being a forthright adult and move on. The system won't care about your story as it will always be easy to compare the condition to disqualifying factors, stop there, and move on to candidates without disqualifying conditions. There will be some RP members with bleeding hearts who will cheer you on. I highly recommend you not bleed with them and focus on moving forward every day to an obtainable life.