tldr: agent says changes cannot be made to a contract for a public university. is he bullshitting me?

While I try to stick away from recruiters, ended up talking with Guangzhou Saintshine Education Service Co. Ltd. and they pointed me towards Guangdong Communication Polytechnic. I'm interested and have continued the dialogue sending him all the forms short of a signed contract.

Earlier he said changes cannot be made to the contract, but I want to put room for signature on each page and a clause for lawful termination of the contract if the college doesn't send me an invitation letter (for example if the agency does) and if they don't send an invitation letter in 40 days.

Is what he said bullshit or can public universities only use a single contract without alterations? Normally I would call bullshit, but with China and schools being state run...