Damaged Shimano 105 shift lever

I damaged my left shift lever when I crashed my Kona recently. It had become
difficult to shift onto the big ring, so I brought it to my LBS. They worked at it,
but, while it would shift okay in the repair stand, as soon as one tried to shift it
while riding, it was nigh on impossible to get it to go onto the larger chainwheel.
The tech at the LBS thinks the only option is to replace the lever (three weeks to
get the part!!).

What broke or bent in the lever that would explain the difference in shifting? Do any
of you know of other options?
--
Andrew Chaplin
SIT IHI GLADIUS SICUT SANCTO MARTINO