Yes, another reason for not wanting to visit Nigeria is that if you want to travel to Thailand from there, you have to fill out a mandatory TM8 health form for monkeypox (it's done online on the Thailand Health Pass website). This is in addition to the yellow fever vaccination requirement.
Parakorn Chanjaru Not everyone is a drunk who wants to splash water for days on end. In most of Thailand, people splash water from around the 11th or 12th to the 15th or maybe 16th. Nearly everyone is back at work well before the 19th. The official Songkran holidays run from the 13th to the 15th.
There are some newish rules exempting foreigners from the need for a work permit if just attending the occasional meeting or signing documents.
More precise requirements should be carefully double checked but I recall simply signing documents does not in general require a work permit. It may be different if the director is a foreign national based in Thailand.