The European airline industry needs real time real measurements in order to ensure we can keep flying for as long as is safely possible.
From that I assume you refuse to accept the weather forecast models and expect to depend on real, continuous measurements of the cloud. But how many aircraft will that require - hundreds to cover the whole of Europe I'd guess.. would they be more precise in giving hourly updated than remote sensing/forecasting? I doubt it.
However, they may also show that the models vastly underestimate the extent and density of the ash cloud, resulting in far more closure of airspace. I assume you would welcome this, or are you simply asking for the answer you want rather than the truth?