Where did you get the driver you note?
I just searched on the epson site and could not find any drivers for that particular printer you listed.
TM-T88v
Fedora does not seem to have the program rastertotmt in cups though other linux distros may.
I can search more if I know where you got the driver ppd file.
Additional:
After doing a bit more searching I found this site
and downloaded the linux dirver on my F39 system.
After unpacking the tar file I tried an installation using the install.sh script and it completed the install after I selected the RHEL 6.5 x86_64 distro.
The files that probably should have been in /etc/cups/ppd were placed in /usr/share/ppd instead.
The file you asked about that seemed missing for you was installed on my system.
$ ls /usr/lib/cups/filter/rastertotmu
/usr/lib/cups/filter/rastertotmu
$ ls /usr/lib/cups/filter/rastertotmt
/usr/lib/cups/filter/rastertotmt
I cannot test the printer since I do not have a matching epson printer but the software does seem it may have been installed properly and just has not been configured which would then place the ppd file in /etc/cups/ppd/