No, they do not perform similarly in gel. One expands and fragments. One yaws and fragments. The first video is Clear Ballistics Gel which is NOT an indicator or terminal performance and should not be used. The AR15.com videos are generally good. However, if you watched them, how did you come to that those the Horn 75gr HPBT and 77gr TMK are similar?
If you read this thread from the start, I state multiple times that Open Tip Match bullets with relatively thick jackets (SMK, Hornady HPBT, etc.) generally kill fine yet can exhibit variable terminal performance. It is not unusual for most OTM’s to yaw and deviate from the original track after striking a barrier, even light ones. Having said that, you could probably shoot another 20-30 and not have an issue with those bullets.
As for the overall situation and deers reaction, animals shot when utilizing a suppressor often react as they do from archery. What you experienced is not unusual as far as animal reaction goes. Had you shot it unsuppressed it likely would have ran until oxygen and/or blood pressure dropped and been dead before you found it.
I’ve stated this numerous times, for general hunting with .224’s-
1). 55, 62, 64, and 75 grain Speer Gold Dots as well as identically constructed Federal Fusion including the 90gr.
2). Hornady 75 and 88gr AMAX/ELD-M (can be a bit splashy).
3). 77gr Tipped MatchKing
I did not forget any. I did not leave any out. If it’s not one of the above, it is probably because it does not perform like the above.
The 77gr TMK is currently THE .224 bullet for 223’s in soft tissue in the broadest ranges and use.