Jfem: I’m sure you are quite aware that the things frum yidden should or should not do isn’t limited to the Taryag mitzvos.
Avi K: While Rav Soloveichik may have said what you quote him as saying, his cousin, the other Rav Soloveichik (Brisker Rav), said that it is better to go into a church than a reform temple. He went as far to say that it might be Yaharog V’all Ya’avor. The reason he said is because the church is foreign to us, there isn’t a significant chance we would be influenced. As opposed to reform and conservative which are religions similar to ours there is a bigger chance that we may be influenced by their ways, c”v.