The Federation wouldn't necessarily have to replicate White, they could just collect it off of dead Jem'Hadar or take a case left by a dead Vorta.
It would be interesting to learn some hard facts about the consumption rate of the stuff. In "Rocks and Shoals", one vial suffices for the supposed standard two-roles-plus-eight-extras complement of Jem'Hadar for about one day (but leaves them unable to shroud or maintain firing discipline, and is declared unusual/insufficient by one of their number in any case). That vial is handed over two days after the crash; we lack knowledge on whether more vials were handed over during those two days, though, and how long it was since the last dose before the crash. We also fail to get an indication of how many vials are normally handed over for ten troops. The field pack of the Vorta Keevan doesn't look as if it could hold more than a dozen vials, but there might be more stuff inside that gets inserted into the vials at the last minute.
In "The Abandoned", Bashir never gets the specs on correct dosage. His estimates range from a week to a year for a dispenser featuring ten vials but again possibly more stuff inside. On top of the uncertainty, the Jem'Hadar there is an adolescent, with requirements possibly differing from those of adults.
In "Hippocratic Oath", Goran'Agar originally crashed with a three-day dose which he spread out for eight days and then expected to die. It would seem natural and consistent to assume he had but one vial with him, but was it full? We see him hand over full vials, and he then reveals there's only five days of supply remaining. Was it those vials, or is there a further set? If he himself could survive for eight days on a three-day dose, then he probably wouldn't worry Bashir with shortage issues if he did have a further full set of vials for his men. OTOH, he speaks of a 27-day supply which in reality is a 5-day one - that's an odd ratio if one vial lasts for five days!
Taking a Jem'Hadar as a prisoner is about as sensible as taking the crew of a Borg ship as prisoners. Neither is known for surrendering in combat.
But once taken prisoner, surrendering is no longer an issue. And the heroes were able to wean one Borg of the Collective in "I, Borg", with mere captivity. Certainly the captivity alone did not fatally threaten the Drone.
Timo Saloniemi