Hi,
There is no such restriction for the vendors but the restriction exists for the products.
You can create two "product template" in HikaMarket and set the "Access Level" for these templates.
The idea is to set the Access Level to all products of the two vendors.
By using the product template, you will be sure that all new products will follow the original configuration (you do not let your vendors change this field, by removing the "product / edit / access" ACL in HikaMarket).
Using the mass action, you can modify all existing products of the two vendors in order to set the acl.
At this moment, the restrictions will be automatically applied to the products and the final result will be exactly the same.
I note your request in the HikaMarket TODO list and I will see if it is possible to implement such feature but it is already possible to do it using the procedure just above.
If you want more details, do not hesitate to ask.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.