Hospital Billing Fraud

I am engaged to be married later this year. A few weeks ago, my fiance was in an accident which required 3 spinal surgeries and over 2 weeks hospital room and board. He is attempting to get Worker’s Comp to pay this case as it was work related and also is applying for medicaid in the event his claim is denied. To make a long story short, both me and his mom claimed him as a dependent (don’t know why she did when he lives with me) and Medicaid is calling this fraud, we were assured that he can reapply with his proper information (my address) and this will go through…

My question is… if workers comp and medicaid both deny his claims (unlikely but possible) when we marry later this year will I then become responsible for his incurred medical costs even though I am not legally his wife at the time of the accident?
I claimed him as my dependent to Medicaid in order to prove he was financially incapable of paying. He has no income and I support him which is basically what I had to say in a letter.
Medicaid considered it a “fraud” application because his mom also wrote the same letter – even though she was told not to — LONG story but I am getting a Marie Barone wanna be for a MIL

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