Not if you are smart. Most of what I am going to suggest requires that you remove the webbing and sew it back on, but there are other ways.
First of all: just how reinforced is the connection? If the webbing is just bar-tacked on, I don't think much of that. If it is well reinforced you may not need to do anything.
If you can put a half-twist in the loop before you sew it back on, that will fit neatly over the trekking pole. You may need to use a new and slightly longer bit of grasgrain for this.
Second, what the pole and webbing transmit to the Cuban is tension. If you provide adequate reinforcing at the junction, all will be well. You cannot just go from webbing to fabric without some stress-concentration, so distribute the stress as much as possible. Add a small reinforcing patch (of cuban) to the cuban first, and glue it on. Then sew the webbing on with the two bits of webbing side-by-side rather than overlaid on each other.
If you don't want to remove the webbing - maybe it is well sewn on, then consider adding some reinforcing at the back. Another patch of cuban might be good. Glue it on and then sew through the webbing.
Fianlly, have you considered adding a small loop of 1/4" webbing through the existing webbing, sized to fit over the tip of your trekking pole? That would require hand-sewing, but it leaves the original tarp untouched and can be 'tuned' to your poles.