Though, if you have a surround-sound setup you may get Audio-Delay/Reverberation when connecting to TV because the TV & AVR-Receiver audio is slightly out of sync, And, the cheaper AVR-Receivers (oh say, Denon) may not have a separate Optical Audio Out/(Pre-Out) because it is cheaper to build AVRs that way.
As to your 3rd-party LE-Audio Transmitter, I don't think that Oticon hearing aids are capable of pairing with that device.
This below may be useful for you, or Not? AI Overview Hearing aids are paired to cell phones using the
standard Bluetooth technology, with specific protocols like ASHA (Audio Streaming for Hearing Aids) on Android and the Made for iPhone (MFi) feature on iOS devices enabling direct audio streaming and advanced connectivity. While ASHA uses Bluetooth Low Energy for efficient streaming to Android phones, MFi devices leverage Apple's proprietary system for iOS compatibility.
AFAIK, this is not possible.
You need either (1) Oticon TV Adapter as @pvc said or (2) BT LE Audio transmitter (for example, Floogo FMA120). I do not know if the FMA120 works with TVs (Its a USB device). I've seen some cheap Oticon TV Adapters in eBay
BT LE Audio and BT LE (which is what you have) are not the same