Can I connect the earbud out on a FM receiver to my iPhone 5?

My church has a set of FM receivers that use earbuds for folks with hearing difficulty. I have hearing aids that are iPhone compatible. Can I use a male/male 3.5 mm cable to join my iPhone 5 (earbud out) and the FM receiver (earbud out) and hear the sound in my hearing aids? I've also seen an adapter 3.5 mm to lightning. Might that be an alternative?