a lot of financial aid
Which financial aid have you got in mind? East Germany was basically cleared by the Soviet Union. The Marshall Plan went mostly to the UK and France, only a small part (11%) went to West Germany.That money is worth a lot more nowadays.
lot of money we got for
That's politically rather naive POV, the money was essentially a defence against the Soviet Union. worth a lot more nowadays.
About 12 billion, so not much.Germany severely limits double citizenship.
Apart from that I cannot see a real obstacle if they have lived here for years.
1) Jus sanguinis (latin for blood ties or right of blood), this means u get citizenship if one of your parents is a citizen of country X. 2) Jus soli (latin for right of the soil), which means u get citizenship by the territory you are born on.
Both countries the USA and Germany nowadays have a mix of those, Germany had 1. back in the day and then introduced 2. over time, also special foreigner laws like getting a permant residency permit quiet eaily after you have been there for 8 years.
SEA especially Thailand has still only 1. so it's quiet impossible to get permant residencies till today - but fear not, you can bribe urself in paying money and its called the thai elite card -.-
Stop making up alternative facts.