L1b extension individual

Hi Team,

I am currently on L1b and the visa expires in May 2022. I recently entered US and my i94 is valid till May 2022.

I asked my employer to renew L1b visa while in USA. But they are suggesting, raising a L1B individual petition can result in RFE or Denial. they are asking me to travel to India and get stamped on new L1B blanket.

if i go for individual L1B and get a denial. can i reapply in blanket immediately. For that can I do It while being in USA?

Is Canada or Mexico an option for stamping?

If Anyone in same boat please share your experience