brighterdays,
According to this bone specialist who ran the clinical trials on reclast about 22% of people on the 5mg dose of zolendronate by infusion have an intense adverse reaction. I'm just reprinting his advice on administration. I don't know your dose but would assume 4mg. Reclast is 5mg.

"I have prescribed a lot of Reclast (zoledronic acid), which to my knowledge is always administered in an infusion center, and not in a physician's office.

My strong recommendation based on my knowledge of bisphosphonates (given that I helped to develop three of them, and treated 13,000 patients in phase 3 trials with them) is to have the infusion center dilute the 5 mg of zoledronic that comes in 100 mL of D5W into 500 mL of NS, and infuse the now 600 mL over 60 minutes. Making the drug more dilute and administering it more slowly significantly improves the renal safety for N-containing bisphosphonates.

I also strongly recommend that the infusion nurses give the patient 650 mg of acetaminophen (Tylenol) at the time of the infusion, and that the patient take that same dose with dinner and at bedtime the day of the infusion, with all 3 meals and at bedtime the day after the infusion, and a final (7th) dose of acetaminophen with breakfast the 2nd morning after the infusion. These 8 doses total of Tylenol reduce the chance of a symptomatic APR (Acute Phase Reaction) from 22% to < 1%.
Best, endodoc"
The innovative suggestions of lower dosing are, in my thinking, a better bet. But your doctor may be reluctant to agree, wanting to give you the best protection against bone metastasis.
There is the additional risk you mention of osteonecrosis and atypical femur fractures.
If you haven't had the tumor tested for it's unique mutations, you should. It can give you a very good idea of where those mutations are likely to metastasize. You should have that information in any case. It doesn't require a new biopsy because that material is held by law.