Something

exten => _164.,1,Set(dialto="")
exten => _164.,2,Set(numreg=${ENUMLOOKUP(+${EXTEN:3}|ALL|c||e164.org)})
exten => _164.,3,GotoIf($[${numreg} > 0]?4:20)
exten => _164.,4,Set(i=$[1])
exten => _164.,5,GotoIf($[${i} <= ${numreg}]?6:19)
exten => _164.,6,Set(dialstr="")
exten => _164.,7,Set(info=${ENUMLOOKUP(+${EXTEN:3}|ALL||${i}|e164.org)})
exten => _164.,8,Set(tech=${CUT(info|:|1)})
exten => _164.,9,Goto(sw-6-${tech}|10)
exten => _164.,10,NoOp(Finish switch-for-if-enum-4-5-6)
exten => _164.,11,GotoIf($["x${dialstr}" != "x"]?12:16)
exten => _164.,12,GotoIf($["x${dialto}" != "x"]?13:14)
exten => _164.,13,Set(dialto="${dialto}&")
exten => _164.,14,NoOp(Finish if-if-for-if-enum-4-5-7-8)
exten => _164.,15,Set(dialto="${dialto}${dialstr}")
exten => _164.,16,NoOp(Finish if-for-if-enum-4-5-7)
exten => _164.,17,Set(i=$[${i} + 1])
exten => _164.,18,Goto(5)
exten => _164.,19,NoOp(Finish for-if-enum-4-5)
exten => _164.,20,NoOp(Finish if-enum-4)
exten => _164.,21,GotoIf($["x${dialto}" != "x"]?22:26)
exten => _164.,22,ChanIsAvail(${dialto})
exten => _164.,23,GotoIf($["x${AVAILORIGCHAN}" != "x"]?24:25)
exten => _164.,24,Dial(${AVAILORIGCHAN}||T)
exten => _164.,25,NoOp(Finish if-if-enum-9-10)
exten => _164.,26,NoOp(Finish if-enum-9)
exten => _164.,27,Goto(default|hang|1)
exten => _sw-6-.,10,Goto(_164.|10)
exten => sw-6-,10,Goto(sw-6-.|10)
exten => sw-6-iax2,10,Set(dialstr="IAX2/${info:5}")
exten => sw-6-iax2,11,Goto(_164.|10)
exten => sw-6-sip,10,Set(dialstr="SIP/${info:4}")
exten => sw-6-sip,11,Goto(_164.|10)