The protocols he suggests look like good ones. Squamous cell carcinoma is a difficult and rapidly growing cancer.
First, the study quoted in the post is a mainstream one and they do not have a very good track record of reliable results when it comes to studying natural supplements, vitamins or minerals. The studies are poorly designed, sometimes on purpose, and do not take into account the other supplements and dietary items which participants may be taking or which may be needed. Such as iodine when it comes to selenium.
Second, the study pointed to a possible increased risk of ACQUIRING squamous cell carcinoma. You mom already has it.
Third, selenium is essential for proper utilization of iodine and I consider iodine to be a must when fighting cancer. The best form of selenium for fighting cancer is methylselenocysteine - which is not the form utilized in the study.
Also, you should be able to find the Beck type machines at reasonable prices.
EDIT: Where is your mother's squamous cell cancer located? If it is on the skin, have you heard of the eggplant cure?