Ask Mr. Smarty Plants

Callistemon rigidus, Bottlebrush is native to Australia, and therefore falls out of the realm of our expertise. The Lady Bird Johnson Wildflower Center is dedicated to the growth, protection and propagation of plants native not only to North America but to the areas in which the plants grow natively.

The article linked above says that Bottlebrush grows from 2 to 8 ft. tall, with a 6 to 10 ft. spread. Since the roots of most trees spread out two to three times the circumference of the tree top, it would seem that they are going to bump up against the foundation 2 ft. away. How aggressive those roots would be toward that foundation, we could not find out. While the tree is hardy to USDA Hardiness Zones 10 to 11, Hidalgo County is in Zone 9b, and the tree would probably be all right with that.

We have no way of knowing if your Board is correct, that the tree would damage the foundation, but since the tree is probably still small, and not native, you might get along better by purchasing another small native tree and planting it farther away from the foundation. The best idea in that respect is to find out in advance what the Board considers an optimum distance. Measure twice, dig once.