Cutting Nails During the Thirty Days of Mourning for a Man's Immersion

Can a man be lenient in having his nails cut by another during the thirty days of mourning for the purpose of immersion after seminal emission?

It is forbidden with a tool but permitted with a change.

Ruling of the Shulchan Aruch, Siman 340, Seif 7: "And a woman whose immersion occurs after seven days, within thirty, if she takes her nails with her hands or teeth, she does not take them well, but she should tell a non-Jew to take them with a razor or scissors. And the Rema wrote: not only a non-Jew, but also an Israelite, and this expression is taken from Chol HaMoed." And this is specifically for a woman's immersion, but for a man's immersion, it is written in Biur Halacha, Siman 88, DH "And thus the custom has spread": "And know further that what is doubted in Shaarei Teshuva regarding a barrier in immersion after seminal emission, I found in the book Eshkol, which we have now merited to its light, that it is explicitly written that a barrier does not invalidate this. However, if there is a barrier on most of the body, it implies there that it invalidates also in this case."