I guess my neighbor tried one of those youtube solutions.  He found 4 sockets in his toolbox which almost fit over the locknuts, he proceeded to sledgehammer them on the locked nuts.  The ridges in the sockets dug in, the more he hammered the further they dug in.  Then he got them off and got new (non-locking) lug nuts.  Then he brought me the jammed socketnuts and asked me if I could salvage the sockets.  I got them off but it took WD-40, a MAP torch, a vise, a sledgehammer, and a suitable drift.

I happened to run across one of the videos I mentioned...
Youtube video on removing locknuts...

Yes, welding something to the stuck wheel lock bolt is what I remember seeing in the past.

Can't help with personal experience but I did see a YouTube or two about that problem. Welding and angle grinders are not nice to alloy wheels, but if your winter tires are on steel rims you might have a chance. The guy on the video had some old alloy rims to sacrifice. It was along time ago, but I think he welded a large not onto the lock

Greetings;
In swapping out my winter/summer rims on my 2015 MCS, I have 2 wheel locks that are either torqued on ridiculously tightly, or have corroded and seized in place.  I cannot loosen these by way of the wheel lock adaptor ( it just breaks ... I've gone through 2 of these in failed attempts, and a local tire company has eaten through 2 more ).  

I am looking for any viable solution at this point.  

I am considering seeing if someone can weld the wheel lock adapter to the wheel lock (bolt), but space is very tight.  
Any other experiences or insight into this problem is much appreciated, as one flat tire and I am in big trouble.  

Thanks Everyone,  
TAS