How's your paper coming along, Lisa?
If you have time to read a slim (but dense) book as part of your research, may I suggest
The Christian Witness to the State? It provides a theological basis for prophetic proclamation to a secular government, and sets reasonable limits for sound theological reasons. I think you might find some of its ideas analogous in the area of religion and business.
One other thing that would be important to consider WRT the UN Declaration is the difference between an outright prohibition, enforced by such things as censorship, seizure of property, fines or imprisonment, and the giving or withholding of state benefits, such as public funding or tax breaks. When professions are licensed by the state and given special privileges, do those who choose to enter those professions do so with the understanding that they, in turn, owe the state certain responsibilities? That has certainly been a part of traditional professional ethics in the legal and medical fields. OTOH, even trained and licensed professionals have limitations and talents - areas of greater and lesser competency. While it is considered unethical to turn away a patient or client because of their religion, it is also considered unethical to take on a case outside the professional's area of competence. Many professionals limit their practices in such a way that they simply do not get involved in areas of practice that would cause them to face ethical dilemmas of providing services they find objectionable.
So WRT the two cases currently working their way toward the SCOTUS, if the photographer had not photographed weddings and similar events, or if the doctor had not provided AI services, the issues of their refusal to serve particular clients/patients would never have arisen.
Personally, when I went into the legal profession, I had high hopes of keeping my hands clean from such messy ethical issues as divorce, but found myself gradually pushed in that direction as a specialty. I found the moral struggles I went through during those years particularly formative. Although I am now retired from law practice, I have found that those ethical struggles have prepared me in profound ways for my new "career" in ministry. I am glad I had to face nitty-gritty day-to-day ethical issues where my values and my clients' values were different. By the time I retired, I had learned, rather than refusing a client, to tell a potential client honestly and personally when I thought my own values and feelings might interfere with my ability to represent them as effectively as someone else. I don't remember having to turn down a case, because the client could see that I was not the right lawyer for them.
The doctor in the case going up to SCOTUS had an exclusive contract with her patient's insurance carrier. That is an analogous business position to the holder of a state monopoly. The patient could not obtain the services her insurance policy entitled her to receive because the doctor discriminated against her. Ethically, I think she violated her obligation to the insurance company. If she had not gotten into an exclusive contractual relationship with a company prohibited from discriminating, she would have had a better ethical basis for taking her stand. By taking the exclusive contract, though, she compromised her ethics. She took on an obligation to offer the same services to all their insureds. Perhaps at the time she made that contract, she didn't understand what it would entail (Jephthah might be an analogous biblical story), but the die was cast at that point. She gave up her option to simply refuse and make a referral to another doctor, since no other doctor could provide the services under the patient's insurance plan.
If she'd been smarter, she could have gone to bat for the patient with the insurance carrier and asked them to cover the procedure under another doctor, but that would have jeopardized her lucrative economic position with the insurance company. They might have used this as an occasion to terminate her exclusive contract. Being willing to accept the economic consequences is always a consideration when making ethical choices in business, even in the clear cases, like the choice to cheat or not to cheat. It is no less a consideration in cases where different people in society have different ethical and religious values.