I feel like it's that thing with pgp when you miss a - or something. or accidentally also copy the LR after the final dash more likely and it pukes on you

But in this vein... having the key is all well and good, but do we know where the code is hosted??

Successfully imported keys into openkeychain and verified the dev pgp key and apk hash

I'm still unable to. Did you change the ext of the file to .txt? Even that didn't work for me.