Late RMD

I am trying to file my partner's taxes (not married filing separately). She passed away in Feb 2020. She's been taking RMD's since 2017. It looks like she reported her 2018 RMD on her 2018 return but it looks like it wasn't actually distributed to her until Jan 2019. I have the 2019 1099-R showing the distribution. Since she reported it on her 2018 return as if she received it by end of 2018 do I still need to report it on her 2019 return? I'm already reporting her 2019 distribution which she did take in 2019. I've read about form 5329 for requesting a waiver. Is that what I need to do? Do I not put the RMD on her 2019 return since she paid the tax on it in her 2018 return?