@Janet_52square the blog post (the one that @mrbadger42 linked to) links to this page:

https://labornematadi.com/predicateur/vance-boelter/

which appears to be a list of sermons apparently given by Boelter in a church in Matadi*, in the Democratic Republic of the Congo (which, the USA Today article mentions that he did some business there).

[*] based on their contact info: https://labornematadi.com/contact/
[edit: accidentally thought this was an address in the neighboring country of the Republic of Congo. It appears to be DRC.]