(iii) a minor otherwise capable of rendering informed consent, then it shall be subscribed to in writing by both the minor and his legally authorized representative. The giving of consent by a legally authorized representative shall be subject to the provisions of subsection B of this section. If two or more persons who qualify as legally authorized representatives and have equal decision-making priority under this chapter inform the principal investigator or attending physician that they disagree as to participation of the prospective subject in human research, the subject shall not be enrolled in the human research that is the subject of the consent. No informed consent form shall include any language through which the person who is to be the human subject waives or appears to waive any of his legal rights, including any release of any individual, institution, or agency or any agents thereof from liability for negligence. Notwithstanding consent by a legally authorized representative, no person shall be forced to participate in any human research if the investigator conducting the human research knows that participation in the research is protested by the prospective subject. In the case of persons suffering from neurodegenerative diseases causing progressive deterioration of cognition for which there is no known cure, the implementation of experimental courses of therapeutic treatment, including non-pharmacological treatment, to which a legally authorized representative has given informed consent shall not constitute the use of force.