Can Aliasing Happen in Laplacian Pyramids?
The reconstruction will remove aliasing, no matter which filter kernel is used.

The lower layer of the 2-layer Laplacian pyramid on page 8 of the Toronto lecture notes, adapted here:

Figure 1. A 2-layer Laplacian pyramid.

can be redrawn as:

Figure 2. An alternative presentation of the lower layer of the Laplacian pyramid of fig. 1.

This layer is an identity operation: what is subtracted is also added. This allows to draw the next (and in this case the only) layer above it the same way and it also can be identified to be an identity operation. And so on until the whole process becomes an identity operation.