Problems with artists

Please merge;
http://www.setlist.fm/setlists/schmidt-33ded429.html
http://www.setlist.fm/setlists/femme-schmidt-63c20e77.html
Second is correct.
Sources: https://de.wikipedia.org/wiki/Femme_Schmidt
http://femmeschmidt.com/

I can't add this artist
https://musicbrainz.org/artist/7aaf5c90-9691-4ed7-8916-491d4900727f

http://www.setlist.fm/setlists/memoriam-6bc1e606.html

is

http://www.setlist.fm/setlists/memoriam-6bc34ab6.html

thanks

Sirs,
I've got a question: Musicbrainz knows the artists Nico Webers: https://musicbrainz.org/artist/69473234-74ab-4172-8db7-45342fcadb2a/details
He is the lead singer of the band “War on a Harlot's Mouth” (https://de.wikipedia.org/wiki/War_from_a_Harlots_Mouth). Sometimes he joins the band “Jennifer Rostock” live for one or two songs. I tried to import him to setlist.fm, but it seems that this is not possible.
So I can not use the @With-, but only the @Info-tag. This is the situation for several years now.
Why is it not possible to import him as a single person?

http://www.setlist.fm/setlists/the-lemonheads-punk-band-3dacd87.html
http://www.setlist.fm/setlists/the-lemonheads-1bdacd84.html

please merge

Please merge

https://www.setlist.fm/setlists/howard-jones-6bd6ba32.html
https://www.setlist.fm/setlists/howard-jones-7bd6ba30.html

https://www.setlist.fm/setlists/howard-jones-6bd6ba32.html

is an English musician, singer, and songwriter. He had ten top 40 hit singles in the UK between 1983 and 1986, including six which reached the top ten, and his 1984 album Human's Lib went to number one.

https://www.setlist.fm/setlists/howard-jones-7bd6ba30.html

is an American metalcore vocalist, best known as the former vocalist of the bands Killswitch Engage and Blood Has Been Shed, and as the current vocalist of Devil You Know.