i really wanted to say this to them. they think they the expert on modern testing and stuff because they did it during an era where stuff was much simpler overall.
The principles and practice remain the same, regardless of time. The tools may be different, but the end goal, the procedures are all standard and have been for decades. Beta / alpha /. combat testing all share the same tasks / goals, irrespective of when.

Your job is to test, quality check, look for bugs, problems, tuning, in the case of alpha / beta, the old phrase test to destruction comes to mind "Heres my latest build, see if you can break it , log what you find and tell me all about it."

The task and the discipline are the same.