She is renting the apartment , he is her guest , it is her responsibility. If he were renting the apartment , it would be the landlord/juristic persons responsibility. That is how it was explained to me.
In your case , your girlfriend is responsible for submitting the TM30 and would be subject to a fine if ever there was an investigation . Book into a cheap hostel or hotel for a couple of days , and get a TM 30 from them.
I had to set up an online account for my ,90yr old father in-law in order to submit an online TM30 when we stay at my wife's place in Thailand. Previously my wife was able to fill out the TM30 at the local immigration office . A couple of visits ago they refused her because her father was listed as the head of the household on the house book. It had never been a problem in the past .The online TM30 is a cumbersome, counterintuitive mess , and I am never sure if I have filled it out correctly.
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