My other half has a gluten intolerance but has given up ordering special meals because they're generally unappealing, catering for the most acute case possible. Instead she works around the existing onboard menu.

I'm not aware of them loading gluten free blinis. My OH sometimes takes her own gluten free options onboard with her, however pre=prepared blinis generally need to be warmed up to properly enjoy them. The alternative (speaking as a gluten tolerant individual) when you have caviar but no blinis is simply fresh white bread which has a relatively neutral taste. Flavoured, even grained bread tends to get in the way of enjoying the main ingredient IMHO. The option of last resort is melba toast: frankly I take my caviar commando in that circumstance..