To get back on topic - I contacted a few of the airlines who are offering E3 sponsorship from the list previously posted in this thread. Most completely ignored my correspondence. Piedmont was the only one that wrote back to say they were interested, and PSA responded to say they specifically do not sponsor applicants requiring an E3 Visa. The rest (e.g. Compass, Envoy, Mesa, SkyWest, ect) were all silent.
Can anyone provide an update as at August 2018? TIA.