I was trying to put together a last minute trip to SAN this morning and noticed great award (Web Special's) on AA from PDX to SAN for 9k (out and back). Aren't the Web Specials supposed to be visible to other OW carriers award programs? They often pop-up on BA and IB, but a little bit more expensive with Avios as they are distance-by-leg-based awards. However, Alaska doesn't feature these AA awards in their search, especially on west coast routings.

Any idea as to why those AA awards are visible to other OW carriers through their respective loyalty programs but not Alaska?