As of version 4.0.4, this client uses an individual peer_id, so it's okay to run both BiglyBT Extreme Mod and qBittorrent at the same time (but note both programs cannot share the same listen port). As of version 4.3.0, anonymous mode has no effect on announce requests for private torrents, so enabling it shouldn't be a detection vector.
This client emulates the following settings, so make sure your real qBittorrent 4.5.5 also uses them:
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