Please contact a personal injury attorney in Hawaii. In New York if you endorse the check it would constitute settlement of all claims; unless the check states what it is for (ie. property damage only) or a restrictive endorsement (ie. partial payment, not for personal injury, etc.) on the back of the check.
Most attorneys are very glad to answer a question or so. As an aside, major injury is a relative term. Seek out the appropriate medical attention.
I am licensed in Nevada, but this answer should apply in Hawaii as well.
Did you sign anything before getting the check such as a settlement agreement? If so, this may be for property damages only or for all damages arising out of the accident. You should check that document if there was one. You can also look to the check itself to see if it is limited to property damages or all damages arising out of the accident.
If you are injured, you should contact and experienced personal injury to assist you in the case.
Hope this helps.
/s Donald Kudler
This answer does not create an attorney client relationship and does not constitute legal advice, but is solely the opinion of a Nevada Attorney.