Can baby sleep in rocker?

I’m so confused ? My baby has acid reflux and he CANNOT sleep laying on his back. He cries and fusses and cannot fall asleep. I explained this to his pediatrician and after trying a few things like medication and switching formula, he tells me to have him sleep in his car seat or rocker/swing? But literally EVERYWHERE it tells you not to do this for risk of SIDS. Have any of your pediatricians told you this? Do you have any suggestions for babies who require elevation to sleep? Halllp.