Questions like this that are about statistical methods or statistical procedures will be addressed faster and get more attention if you post them in the Analytics>Statistical Procedures community.
First, note that the GEE method is robust to not specifying exactly the right clustering structure, so it is not unreasonable the use the GEE model from the code you showed in your first post.
However, if you particularly want to use an ALR model to estimate log odds ratios, and if your data consists of patients clustered within physicians and with multiple observations from patients, then you need to change your REPEATED statement options. Instead of TYPE=EXCH, which requests a GEE model, specify SUBJECT=MD (I assume that MD is your physician indicator) then specify LOGOR=NEST1 and SUBCLUSTER=PATIENT:
repeated subject=md / logor=nest1 subcluster=patient;
While LOGOR=NESTK (with SUBCLUSTER=PATIENT) or FULLCLUST are other possible structures, they are probably not feasible since you indicate that, on average, there are 100 patients per physician. These structures would probably require the estimation far too many log odds ratios, and in any case would probably not be useful.
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