Thanks to the natural defences that the Orientemian soldiers get in the mountains, and their own somewhat amateur fortifications, the planes are not able to seriously damage the mountain camps, while also evading the bullets of the advanced sub machine guns, and anti air. And since they’re Close Air Support, it would be incredibly easy for the weaponry to hit the planes precisely, also before much damage could be done. And every time a plane falls to their bullets, they would scrap as much as they could from it, to get more weapons, ammunition, or just to improve their fortifications. And despite the Nigerian troops being ready for mountain attacks, and therefore be able to defend themselves very well, they would be unable to attack the Orientemian, without having a clear disadvantage, thanks to the many hidden Orientemian camps in the mountains.
No Orientemian troops follow them to Djibouti, so almost none are killed there. Instead they completely surround them, also navally, where ships are surrounding Djibouti, while still staying long away enough not to be able to be fired on by the artillery. Only from time to time would a few ships quickly sail within distance, bomb the forces of Djibouti, and sail away again before they would be able to retaliate, in a seemingly random pattern. This way the Orientemian forces are starving the Nigerians in Djibouti, while also navally bombing them. Anti air is also set up on the ships, and in the mountains up towards Djibouti, to make sure that the Nigerian airforce won’t be a threat here.
The Orientemian forces would simply follow the Nigerian soldiers, and Jackal Militia, through the mountains. Making sure that the enemy forces wouldn’t flee out of range, but also making sure that the enemy won’t be able to attack them. At least not with any more success than before. While doing this, they would build small fallback encampments, with basic fortifications, that take no time to build. And they would also continuously fire upon the Nigerian and Jackal forces, giving them no time to gather supplies, and get more ally soldiers. This would give the Nigerians a couple of options. Either they would keep feeling that way, meaning that the last of them would pretty quickly be killed off by the Orientemian forces. They would have to flee West instead, but then the Orientemian soldiers would just follow them that way, up in the mountains, and the exact same would happen. They could flee North, but then they would not only leave their lines open, making it impossible for them to stop the Orientemian soldiers in a push. But they would also all be mashed together, and then advanced jets and bombers would destroy them in just a few sweeps, seeing as they wouldn’t have the resources for good enough anti air to stop them. Or they could simply charge the Orientemian soldiers, and be killed off instantly. Whatever they choose, this would pretty much be the end of the Eritrean front.
Thanks to the openness of the South, every time the “Unterstützungspanzer” even comes near the fortifications, in which the Orientemian soldiers there are stationed, it is easily destroyed by the advanced artillery inside the fortifications, with no chance to evade the strikes. And the Orientemian soldiers would be able to flee closer towards the mountains anyway. You would therefore realistically learn that that is not a good strategy, and that the Unterstützungspanzer should be used differently, or not at all.