My answer may not directly address your question, but it might offer a solution to your problem. I hope that is okay.
We have looked after several reactive dogs and watched YouTube tutorials to learn which approaches might help. Fortunately, there is a wealth of information available on this subject.
Along the way, we also discovered a few things through experience and advice from a dear friend. When a dog reacts strongly, behaves aggressively, or lowers its body while whining in a high tone, it is often acting out of fear.
What works for us is paying close attention to the dog’s needs and preferences, including whether, when, and how it likes to be cuddled. Affectionate contact can promote the release of oxytocin in both humans and animals, helping to create a sense of safety. However, it should never be forced.
We also reward calm and responsive behaviour with treats. For example, we give treats when the dog walks calmly on the leash, comes when called, or sits before going outside.
Building trust takes time, and there is a significant difference between looking after a dog for a short period and caring for one over a longer period. In our experience, predictable behaviour from the pet sitter, affection when the dog welcomes it, and rewards for calm and responsive behaviour work best.
Last but not least, try to find ways to enjoy the dog’s company and preferably to genuinely care for the dog. Dogs are often highly sensitive to human emotions. If you are only doing this temporarily and are perhaps afraid of dogs yourself, that may be something you need to acknowledge and work on as well.