Every time I start one of the games mentioned in the title, the hialgo switch just does the Beep and does not appear the option to inject, ja mechi in the '' GAMES.INI '' but nothing
If you look at the List of Games used with SWITCH, 26 people said that SWITCH does not attach to Sniper Elite V2, and 5 people said that it does. So, maybe these 5 people are mistaken, and it never attaches?

For Battlefield: Bad Company 2 the situation is opposite: it works for most people.

Conclusion: you should be able to fix your problem with Battlefield: Bad Company 2, but with Sniper Elite V2 your chances are slim. 

What can you do? I am not sure: try starting these games in different modes (for example, full screen or windowed, with higher or lower resolution etc.), make sure no other application is running at the same time; make sure you run SWITCH as Administrator...

Also, look at the log files, maybe there are some useful error messages.