Hello, Poco,

Can the Vericolor be processed in C-41? If so, you could use Panalure (without safelight, of course) for standard black and white prints from the color negatives. If not, you could experiment with your favorite B & W developer; it shouldn't take more than two or three sheets to zero in on an approximate exposure index and developing time.
I assume that the Ektachrome is new enough to use E-6. If so, why not just shoot it normally and then make a copy internegative on T-Max 100 and go from there.