This approach could definitely work, the thing you’d need to watch out for is your max cable length is dependent on your clock rate. Here’s a nice chart showing approximations:
And our available clock rates on the RMCs:
You can see this would be doable assuming your sensor can work with the frequency as well. It looks like and RMC200 or possibly an RMC75 would be able to get you the length you need.
Also, here are the help topics I grabbed those images from if you’d like to dig deeper:
https://deltamotion.com/support/webhelp/rmctools/#t=Controller_Features%2FTransducer_Basics%2FSSI_Fundamentals.htm&rhsearch=ssi&rhsyns=%20