How can the seal fail under ware and tear it's not a moving part ?
I would go direct to VX customer services explaining what has happened and who you have been treated by the dealer and ask CS to sort this matter with windscreen reseal and replacement post trim plus arrange a full refund of your hard earned £72.00
If you don't get any joy then try removing staining with wet baby wipes good luck
2012 Antara 2.2cdti 163ps Awd SE Nav Auto in Smokey eye Grey with light Titanium interior. With 19 full size matching spare.
Towing a Bailey Pegasus 554m.t.p.l.m. 1492kg