asterisk users - Jan 2019 - features.conf disconnect and local channels

Asterisk 16.1

This statement appears in the features.conf doc: "Note that the DTMF 
features listed below only work when two channels have answered and are 
bridged together. They can not be used while the remote party is ringing 
or in progress. If you require this feature you can use chan_local in 
combination with Answer to accomplish it."

I need attended transfer and disconnect from features.conf to work. 
Below is what I came up with that seems to work fine. Is there a better 
way? This seems a bit verbose.

[InternalSets]
exten =>298,1,NoOp()
   same =>n,Dial(Local/M${EXTEN}@InternalSets/nj,,H)
exten =>M298,1,NoOp()
   same =>n,Answer()
   same =>n,GoSub(sub-voicemail,start,1(${MITCHIPHONE},${EXTEN:1}))
exten =>299,1,NoOp()
   same =>n,Dial(Local/M${EXTEN}@InternalSets/nj,,H)
exten =>M299,1,NoOp()
   same =>n,Answer()
   same =>n,GoSub(sub-voicemail,start,1(${MLCX450},${EXTEN:1}))

[sub-voicemail]
do some checks and then Dial or send to voicemail.

-- 

Mitch