Pretty simple guidelines for you because you're so allergic. The lowest stainlessgrade that has a chance to work with metal allergies is 316L. There are higher grades than that up to those that start 316LVM. That grade means the nickel has to be contained in the inside of the metal in a way that's inert when inside the body. 316LVM is used in pacemakers and such; it's surgical implant grade. It or titanium will be generally the only body jewelry an allergic person can wear and not react. It's also more expensive. So I don't know that you would even see a stainless pole 316L or higher honestly. All stainless steel has nickel in it; it's just a matter of what state that nickel is in. And 316L, btw, is the grade of stainless used in mall jewelry that you've probably had a reaction to. So if you can't wear cheap stainless body jewelry without going crusty you definitely need 316LVM If you ask what grade of steel they use and it doesn't begin with 316L, it's not rated for use even as jewelry and therefore will have more of those metal compounds like nickel that can trigger a severe reaction for an allergic person. Generally industrial grade steels aren't designed to be in prolonged contact with skin. Obviously for something like pole that's only going to be an issue for the very allergic.
That said, tg xpole might work. As for the finish wearing on it....it does, but not necessarily after a year. It doesn't have that kind of set expiration date. And it tends to wear in spots that get heavy use, like where your top hand always goes.
As far as coating or painting your xpole, I think that would damage the finish and increase the likelihood that the chrome would chip off. If chrome chips or scratches, it can't be repaired, and can have wicked sharp edges that will destroy your hands. Even if you did paint it, you have to remember that taking apart a multiple piece pole for regular cleaning or moving could cause a reaction from handling the uncoated threads and inner parts. And you couldn't paint the threads or joints because it would interfere with the stability or make them lock up. Ultimately, a one piece permanent pole could be your best bet down the line. For now, I would email customer service of xpole and platinum stages and see what you hear back about metal grades. If you can get an exterior finish like tg that doesn't react, I'd go with that. And just use gloves when taking it down to clean or wash with soap and warm water and really scrub down your hands after handling the threads since I'm guessing the interiors of all these poles will be industrial grade steel. A hydrocortisone solution wouldn't go amiss, either (benadryl ointment).
Sorry all my responses have been so wordy!