All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
It was not clear to us from the question the husband's position on his wife's travel to that country, the extent of the need for this travel, and the reason for choosing this country that the husband is cannot enter.
Anyway, we have to point out the following matters:
- A woman's residence in any country, if she is safe therein, is not conditioned upon the presence of a mahram (a non-marriageable man).
- The basic ruling is that the woman resides wherever her husband resides. She does not have the right to travel or reside in another place without his permission without necessity.
- The separation of the spouses for a long time may pose detriments and evils that affect them and their children.
What we are inclined towards in general is that the wife should stay with her husband and the children until it is facilitated for them the residence in a Muslim country together.
Allah knows best.