BT.2020 Colour profile - Video unable to be interpreted/encoded

We manage many thousands of video uploads and recently received a video that despite being converted to a number of different formats (mp4, mkv, mov) continually errored during the transcode (4000 error Amazon Elastic Transcoder could not interpret the media file.).

The video had the following encoding attributes (created on an iPhone 12)
Codecs: AAC, Timed Metadata, HEVC
Colour profile: BT.2020 HLG (9-18-9)
Dimensions: 1080 × 1920

I was able to play the video locally with no issues.

We are using the following preset: 1351620000001-000020 (MP4, 480P, H264, etc) - I tested with a series of other presets on our dev host and none of them could handle this video.

We were able to finally get Elastic Transcoder to ingest the video after taking it into Adobe Premierre and converting it to an MP4 there, with the following changes:
Codecs: AAC, H.264
Colour profile: HD (1-1-1)

I had earlier created an MP4 without changing the colour profile and that failed - so I think it may be something to do with the colour space.
Changing the preset colour space conversion mode to Auto didn't fix this issue either.

Thankfully this is the only one of these that I've seen this week - wondering if anyone knows what the best preset is for dealing with these new colour profiles?