As Victron is based in the Netherlands, I’m sure the engineers are fully aware of the situation. But it might be worth reaching out to Victron support.
I don’t use Node-Red, as I’m favouring Home Assistant. I see from this post: Make DESS aware that PV can be turned off when prices are negative - #4 by ErikBTD
that you can use HA. Why not simply use MQTT to turn off the MPPT controllers when pricing is negative in the same way you do with the PV Inverters you have? The required register and values can be found in the Victron documentation, do a search for ModBus registers or similar.
I think it might mean setting the MPPT mode to 4 (off), you’d need to look into this further.