Before addressing the hardship exemption, can you explain why your Roth IRA withdrawal is taxable at all? If you are over the age of 59 1/2, none of it should be taxable. Even if you are not yet "retirement age," the distributions up to your prior contributions over the 20 years should not be taxable. Have you been tracking your Roth IRA contributions or does the administrator have a record of them? Have you taken prior distributions?
The hardship distribution rules you are quoting generally have to do with employer-sponsored accounts. The ones that pertain to all accounts, like the first-time homebuyer, medical expenses, and qualified reservist, either don't apply to you or have already been used up. In some circumstances, you can take money out of an employer retirement account or borrow from it without penalty, but those options are not available with an IRA.
If you are under the age of 59 1/2 and your distributions are taxable, I am not aware of any hardship exemption for a Roth IRA distribution. However, I would check your own records as well as your retirement plan administrator to see if you have a record of your contributions and prior Roth distributions to see if this distribution even is taxable, even if you are under 59 1/2.
