I interpreted the original ad differently, that the wall was a literal barrier to their illegal intent and the door a metaphor for the legal method of immigration. If their intent was otherwise, the door would have been omitted.
The ‘door” should have involved the process to become a legal citizen, not just a hole in the wall.
But legal immigration would involve simply driving to the border. No need to go on a multi-day quest hopping trains and walking across the desert.
According to the head honcho of 84 (who is a Trump supporter) that’s exactly how she meant it.