Tell application screen is not zoomed
Technical Limits

No, it is not possible to tell one application to ignore the zoom state of the screen.

By complaining the application is taking additional steps to both detect and notify you of the zoom condition; this is not normal.

That the application complains, suggests the developers encountered problems when the screen was zoomed.

It is possible the "Decoder" application is using the screen buffer in some way intrinsic to its purpose. It may be writing directly to memory buffers or using other techniques to display video that rely on the display resolution being understood and constant.

Contacting Support

Have you tried contacting the developers of Decoder directly? Have you logged a bug with their support?

Most enterprise software is highly configurable and may include hidden options to support what you need.