The university did not agree to drop charges against forty students for rule violations, but the charged students themselves voted to accept the agreement under the belief that the overall offer was worth their own sacrifices.
Not including amnesty as a prerequisite is wildly irresponsible. What leverage do they have now? The board can simply say “no”, and send the cops in to arrest anyone who tries to restart the protest.
This isn’t negotiating, this is the students unilaterally giving up everything in exchange for… The ability to ask again, but quietly and in a circumstances where there is no consequences for saying no?