Maybe this would be easier to understand if I knew what the message was and how him not showing up to work would be pinned on you. But just from what you've said on here, it sounds a little shady.
By and large . . .you can refuse but they can fire you . . . they don't require much reason to do that just your resistance to it may weaken your position in the company If they this shady . . . I would start looking for a new gig cause . . I don't think this ends well Rocket River
I would keep copies of all emails and texts about this just in case they do fire you for no reason. If you're here in Texas you can also record your conversations as well without telling them you're doing it. If your concerned about losing your job you need to speak to an attorney. The more documentation you have the better.
hypothetically speaking let's say a certain somebody typed a response to you on CFs but this person is the person in question who may or may not work at that place in question and what if this person is the typing the response right now and may or may not report you as possibly airing this stuff on a hypothetical forum which may or may not exist at least not in this demension