MySQL Select query that chooses something dot something between certain underscores

I have a MySQL column with underscores and between those underscores a domain name (which is anything with a dot, except number.number), and I like to use REGEXP_SUBSTR to extract that domain, but only if there are at least 2 preceding underscores before it.

Examples:

1. Something_Else_Type_XY_Z_26.04.23_website.com => website.com
2. Something_Else_Type_XY_Z_website.com_26.04.23 => website.com
3. Something_Else_Type_XY_Z_26.04.23_website.com_Comment => website.com
4. Something_website.com_Else_Type_XY_Z_26.04.23_Comment => NULL (due to not having 2 preceding underscores first)
5. Something_Else_Type_XY_Z_26.04.23_Comment => NULL (due to not having something dot something that isn't number.number)
6. Something_Else_Type_XY_dfd6869_3_21.12.22_website.com_ZU => website.com

Which regex could do so instead of ... in SELECT REGEXP_SUBSTR(full_name, ...) as domain_name?