Don't support this IPO. It can't harm United if the price drops- no voting rights and only a proportion of the ownership- but nor will a huge share price really benefit them.
If you're interested in owning a piece of the club for novelty's sake as a fan buy one share. It'll be as valuable in the long run as a thousand- they carry no voting rights and you'll never see a dividend from the Glazers.
I hope you can extricate yourself from their clutch before too long.