JW, if the unit is on 134a and it lost the charge, it also ingested copious amounts of air at the leak. Therfore the compressor is contaminated and basically doomed. Why put this customer thru any more expense when she could go out and get a new one or by some dry ice to tide her over.
As we know, air infiltration will turn the R134 to gel, causing a system-wide restriction. Too late to re-charge.