All former employers experience letters needed for GC filing.?

[swetg1]

Hi There, 
My company(************) is in process of filing GC for me, for the same am trying to collate my former employers experience letters, i worked for two companies before joining *********. 
My first company was ******, i contacted for letter and the email reply was that experience letters are not provided for former employees neither by HR nor employees/supervisors are entitled to provide affidavits since there is change in corporate policy. 
I inquired in ********** on this scenario, the reply was that company can go ahead with filing GC with available exp letters, that means ignoring ******* 'experience' and experience letter, is that a good move.? 
FYI- i have almost 10 yrs exp. 
apprx 4 yrs with ********** (has exp letter) 
apprx 2.7 yrs with second company.(got exp letter from this) 
apprx 2.7 yrs with first company, i.e *********- No experience letter. 

H1 max out is 2019. 

Any help is greatly appreciated.

[ashuneel]

Please use company A,B ,C instead of ****.

IF 4 yrs experience is with current employer it does not count towards PERM.