Yes, 何人も空の胃の腑で愛国者たり得ない is valid, but the point of the sentence / what the writer wants to say the most becomes unclear in this sentence, so it could sound a little bit awkward.
何人たりとも、空の胃の腑で愛国者たり得ない
何人も空の胃の腑では愛国者たり得ない
何人も空の胃の腑で愛国者たり得ることはできない
These sentences are more natural.