Well, cet_m01 is starting to annoy me, so I took a look at it in FRED to look for clues as well as any loopholes we might exploit next time we try. And thankfully there are a few things.
First off, the reinforcements that we kinda didn't know we had look like they could be a huge help. It's a wing of 4 Thoths armed with Prom S and Trebs, with 6 waves. That right there is a huge help, the ships and loadout are tailor made for escort which is exactly what we need.
Second, all but one of the enemy wings have no wing threshold. This won't be of much use for the bombers since they'll be killed by capships anyway, but if we could reduce on or two of the 20 wave fighter wings to 1 fighter and leave it alive, it could take a lot of heat off our backs.
Finally, it looks like there's about a 1 in 3 chance that the enemy Leviathan cruiser (Fenrir) will actually defect and join our side. Needless to say, adding 4 AAA beams not to mention a non-essential target to take heat of the Shai would be a huge help, but since it's random we just need to get lucky.
Oh, and one other thing. The massive waves of fighters are not due to us losing, they always appear. It's simply because more and more wings have their arrival cues satisfied, while older wings have a massive number of waves and are practically unkillable. So by the end, we have 4 wings of fighters with 15-20 waves in addition to any that are just arriving. Which is why trying to keep one or two of those waves crippled by exploiting the lack of a wave threshold might be a lot of help.
[Edit] Forgot to mention this: None of the bomber wings (Gebo, Nauthiz & Fehu) have an impossible number of waves, so if we concentrate on them as they arrive we should be able to wipe them out for good. So we should definitely ignore fighters in favour of bombers, since many of the fighter wings have a huge number of waves and will just keep coming.