Glad to hear they're recovering, slowly but recovering anyway. Why dont you try to get PraziPro from Ebay?, i get some myself last year, i'm in Spain and it wasnt expensive. I dont like Sera meds cause of those huge WC you need to do after a few hours of treatment, but they work fine. I have used Tremazol in the past, but in order to try to avoid the WC i did a long bath (6h as they say) with the recommended dose, and that worked fine for me with some retics a few years ago. It was easy, but they were 10cm diameter....not sure if it will work with a beast.
Best regards
Ernesto Roa.