Feeding Crickets to my Tarantula

Last night, I placed the first cricket right in front of my Chilean Rose & my T "Venom" didn't grab onto it right away like he normally does & I noticed the cricket escaped through a hole on the cork bark & I don't know if he buried himself under the soil or dug under just to escape from getting eaten, but I searched everywhere turning over the soil & I couldn't locate the cricket at all. My T did eat the other 2 crickets later that night. Do crickets sometimes run away & burrow under the soil to escape getting grabbed by the tarantula? I did find what looked like 2 dried up cricket carcasses in the soil. Also, when I'm feeding my Tarantula the 2 crickets, I give him 1 cricket to feast on for a while, then place the other one right near him using stainless steel tongs. Should I be placing both crickets in at the same time, or is it ok to feed him 1 at a time. I'm sure if my Tarantula doesn't eat the other cricket right away, he'll eventually grab onto it the next day or when he's hungry again.

They can dig into the soil a little bit, but usually if you T is hungry he will catch it. Yes it is ok to feed one at a time.
The only time you have to be carefull is when your T will start to molt.