welcome home!!! i've had the same infusion company twice now and the first time they said tobra had to be done as an IV drip hang... it sucked. i don't know why, but the next time they gave me tobra in the balls and they worked great... actually more true-to-time to infuse than my other meds!
is it possible its an insurance issue? i think the balls are the most expensive way to do IVs, so if your insurance knows they have the IV drip or another cheaper means, they may just be denying coverage of the balls.
good luck to ya.