My parents are going to visit from Germany and will bring our niece along as well. The route is FRA-DFW-OMA on 5/29 (in) and 6/10 (out). I have 4 unused SWUs left that I would like for them to use to either upgrade the inbound or outbound flight segments from economy to business. None of them have status or even AA frequent flyer numbers. I am a lowly gold.

I read through the upgrade pecking order at flyerguide.com and it looks to me that they are pretty much the bottom of the barrel. Is it realistic to hope that any of these upgrades clear?

The issue, if this has only marginal chances, is that they are better off flying out of a different city in Germany, one that AA doesn't service. If they go through the effort of going through FRA, I would like the chance of success to be somewhat reasonable.

Any thoughts are much appreciated. Thank you!