I placed a 2.89 lb pork butt in crock pot, on warm accidentally instead of low, left to cook for 4.5 hours before I realized it. Internal temp was 122.6 when discovered. Think it's safe to continue cooking on high too at least 165°?
122°F is inside the ‘danger zone’ of 40-140°F, which is where bacteria and such will reproduce well. 4 hours in ‘the zone’ is risky as even if you heat it to kill off the bacteria, there’s still whatever toxins they produced in that time.
I personally like to start my crockpot on high, so I can be sure that it’s heating up and get the food out of the danger zone quickly before I switch it to warm. And it actually saved me about a month ago, when I realized that my crockpot wasn’t actually heating… before I had planned an overnight cook. (So I had a chance to warm it in the oven, then set it on low all night)