This is true only for some countries like United States! In Italy you just need to register as a "italian resident in other country" and tell them where you are resident. And puff! No tax to them anymore.
for me is okay to pay personal tax if you stay in Thailand more than 6 months. In almost every country is the same. The important thing is to avoid double taxation.
what consulate did you try? I think maybe the best solution is to temporarely send the money from the business bank account to the personal bank account. I heard people here said that they did and this get accepted.
se mandi una mail rispondono, a me l'hanno fatto dopo avermi annullato una richiesta. Stai molto attento che al minimo errore o dimenticanza ti possono annullare la richiesta di visa e perdi i soldi, non chiedono correzioni e non possono farle...devi leggere bene tutto e mandare tutto quel che ti chiedono