I have a dynam primo rtf can I use the transmitter https://www.dynamrc.com/products/detrum-gavin-6c-2-4ghz-digital-transmitter in a ROLLING STOCK
Understand that the transmitter you wish to use on some scale rolling stock is not going to work. Basically, Bachmann's only controller that I know of is "Dynamis E-Z Command Wireless DCC Model Railroad Control module, model 36505. It has an Infrared (IR) frequency somewhere in the 300 GHz – 430 THz, while your dynam primo has a frequency of 2.4 GHz or 5 GHz. With that low a frequency it's to slow (data rate) for IR.
Hope this answers your question.