Even with the newer converter on my K2 I woke up to a dead battery! Not happy with this setup! I replaced the battery with a heavy duty then took the bike out for a good long run 60 miles 3 days later tested the battery and it was flickering on the red marker on my tester!!! I bought this setup in January this year (2019) Rock said the new converted would solve this battery drain...well it hasn’t!! I will contact the outlet I brought it from for help!
It is strange that your new battery got drained within 3 days. I mean....even the old converter "only" takes 1Ah/day. That is not enough to drain a new, fully charged battery within three days. So either your new converter takes much more current than the old one, or your battery wasn't fully charged. I suppose the latter one.
Can you check how much current the new converter takes?
New converter could not drain battery so fast, as @Frotie mentioned, please check the current from the new converter.