GOautodial Open Source Omni-channel Contact Center Suite

Try This

[outbound]
exten => _886X.,1,Noop
exten => n,Gosub(pickCallerIDnum,cell${RAND},1)
exten => n,Dial(SIP/${EXTEN}@gateway,32,gCX)

[pickCallerIDnum]
exten => cell1,1,Set(CALLERID=09xxxxxxx1)
exten => n,Return
exten => cell2,1,Set(CALLERID=09xxxxxxx2)
exten => n,Return
exten => cell3,1,Set(CALLERID=09xxxxxxx3)
exten => n,Return
exten => cell4,1,Set(CALLERID=09xxxxxxx4)
exten => n,Return
exten => cell5,1,Set(CALLERID=09xxxxxxx5)
exten => n,Return

or create new dial plan entry with different dial code in ext.conf

For Camp1
exten => _1NXXNXXXXXX,1,Set(CALLERID=<insert callerID here>)

For Camp2
exten => _2NXXNXXXXXX,1,Set(CALLERID=<insert callerID here>)

For Camp3
exten => _3NXXNXXXXXX,1,Set(CALLERID=<insert callerID here>)

For Camp4
exten => _4NXXNXXXXXX,1,Set(CALLERID=<insert callerID here>)

For Camp5
exten => _5NXXNXXXXXX,1,Set(CALLERID=<insert callerID here>)

Change Dial prefix in each Camp.