I agree that the risk is very low. Perhaps citing this paper may help.  Allergic_Sensitization_to_Nickel_and_Implanted.4.pdf

My toxicology view is that EDTA is barely allergenic and unlikely to cross react with ethylene diamine. I would be interested to learn if there is any...

Wise advice. Even with nickel, the relevance of allergy to it is difficult (Kimber and Basketter, 2022 in Dermatitis reviewed the topic).  All...

As an adjunct, even if you/your patient can get through and do the full series, the high degree of cross-reaction between the main dye agents means th...

Health warning - I am a non-clinical toxicologist member of BSCA. Cross reactions can be complex; your first assumption is reasonable, the primary all...

Also received it. As a non-clinical member, I expect to input only rarely....David

Regarding the benzocaine in condom point, in addition to penile dermatitis, I wonder what the risk might be for the partner.