Sounds like a lot of legitimate cautious advice given the history and and a few getting the I told you so comments on record.
Essentially stock motor with decompression pistons is less likely to detonate.
Stock
ECU. Stock fuel trim running a knock sensor.
It will just be down on power.
If it were an engine with significant mods, cams, injectors etc then it would be a different story.
It's pretty normal to put a few kms on a rebuilt engine prior to tuning.
Just treat it with respect. I'd be running 98 octane as a precaution. Stay away from the drags and comps though until it's been on the rollers. If anything sounds odd park it and get it looked at.
Hopefully you've seen the end of the issues and can finally enjoy it.