When presented with high lift / shorter duration or low lift / longer duration for EFI, a good general rule is to pick lift if possible. The cam recommended by the tuner may not be all that different from the HOT cam. It's got less lift and slightly more duration. The difference in ICL (1 degree) could disappear in manufacturing. The HOT cam has fairly mild ramps and I'm betting the Lunati version is the same. I'd have no problem running the HOT cam.

And I think your tuner would choke if told I'm using a 302 with a smaller cam in a Suburban. My truck has 3.42's and it tows a trailer. I originally built the engine with an LT4 stock cam for an S10 Blazer but changed to the Marine cam before the engine was installed. Short stroke engines tend to like smaller cams.

The HOT cam has little overlap and makes strong and steady vacuum. In a heavy truck with an automatic it will prefer a looser converter. If you're in an area with lots of hills you might tune for faster unlock of TCC on the highway and let the converter work for you. You might also tune for 4 -> 3 downshifts at lower throttle angle.

Put the biggest dang cooler you can on that transmission. The trans will be expected to shift and in some cases a looser converter generates more heat.

Do your prep work on that Holley TBI. I don't know how old it is but you need to be sure you have it in good shape before tuning begins. Understand what injectors are installed, make sure the throttles close properly, and make sure the IAC works.