Please get some POLYVISOL enfamil (no extra iron) and give three drops to the younger bird and four to the older bird in beak once a day for a week then taper off the next. This is a liquid childrens A-B-D vitamin (vit A deficiency is usually also present with eye and respiratory disorders and articles usually advise a supplement). See here;
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/206922.htm
Dont count on the piperazine having gotten all the worms because you dont know what worms they might have had (Piperazine is not a broad spectrum wormer but only effective on ascarids). Piperazine is thought to exert curare-like effects on susceptible nematodes, thereby paralyzing or narcotizing the worm and allowing it to be passed out with the feces (it does not kill them and will not deal with all stages of the worm).
See the chart on this page:
http://www.aviagen.com/docs/Intestinal Worms_TUVol1.pdf
Read here on the common worms and treatments:
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/202800.htm
excerpt regarding piperazine:
"....Piperazine compounds are relatively nontoxic and widely used against ascariasis. Several piperazine salts are available internationally. Because only the piperazine moiety is efficacious, doses should be calculated based on mg of active piperazine/bird.
Piperazine should be completely consumed by birds within a few hours because only relatively high concentrations of the drug eliminate worms It may be given to chickens as a single dose, 50-100 mg/bird, or at 0.2-0.4% in the feed or at 0.1-0.2% in the drinking water... There is increasing evidence of significant piperazine resistance in the USA...."
Is there anyone you could get a sufficient quantity of ivomec Eprinex from to treat these two birds? This is a broad spectrum wormer (will get everything really except tapeworms) and very safe to use with a bird that is ill.