I see. If your position is truly ending because of the employer's business needs and your claim of discrimination is not very strong, then the offer may be reasonable. However, since you have a charge of discrimination pending with the EEOC, there would typically be an inference that the employer is terminating your employment in retaliation for filing the charge, which would support a new claim being filed with the EEOC for retaliation since that is also prohibited by federal law.
If the employer cannot prove that they would have terminated your position even if you had not filed a charge with the EEOC, then you could prevail on a claim of retaliation in addition to your claim of discrimination, so you must carefully consider whether the employer's stated reason for terminating you is legitimate, or whether it may be a pretext for retaliation, supporting a new claim against them.
If it is, then I would not seriously consider their offer. In addition, if your claim for discrimination is sound, the offer would not typically be reasonable if you have suffered lost wages and benefits or may be able to seek punitive damages because you can prove willful discrimination.
Since they are not providing you with any guarantees after the 6 month period, you may wish to consider presenting them with a counter-offer for a sum of money in addition to the 6 months of disability as a settlement of your claim.
It would be best though is you consulted further with a local employment law attorney to closely review the merits of your claims in order to advise you as to the strength of your claims. If you have viable claims of discrimination or retaliation, then the offer does not appear to be very reasonable.
Finally, if you are disabled, you may wish to consider filing for social security disability as that could pay benefits even if you are not entitled to benefits under the employer's plan.
I hope this helps clarify the situation for you. Please remember to rate my service once you have all the information you need so I will be compensated for my time from the deposit you posted with this website. If you have any other questions, please ask me – I’ll be happy to respond. Thank you!