Source generator for Satellite Tuner input
So, what you're proposing is that for the satellite and terrestrial signal testing you build your own signal source – which is fine.

That's what we call Software Defined Radio (SDR) and it's been on the block for quite some time. You'll find that you really shouldn't be putting your time into developing your own analog frontend – there's existing SDR devices that do exactly that, and believe me, this whole dealing with RF requires intense analog design and testing, and for TV standards, you need significant digital bandwidth to push through your 30 MS/s. Even if you work for food, letting you design that isn't cost-effective; buy existing SDR hardware.

You're doing a few mistakes in your LO calculation (your DAC doesn't produce an IF signal at IF=30 MHz), so you also might be in a bit over your head, too. In that sense, I might add that Michael Karas' comment might be the most time- and cost effective answer: getting someone to do it for you might be cheaper than learning all the SDR stuff yourself on company time.

You can then use commercially or freely available tools to generate the baseband signal you want to modulate up to the carrier frequency. Disclaimer: I'm affiliated with the GNU Radio Free Software project, with comes with gr-dtv, a module containing DVB-T, -T2, -S and -S2 transceiver infrastructure. I'm also affiliated with Ettus, which produce the USRP line of software defined radio devices. But I'd honestly recommend you go for GNU Radio (maybe try my live SDR USB drive image) and an Ettus B200 for your signal generation needs.

You could generate the desired signal once in GNU Radio and save it to a file, and then use GNU Radio to loop that file and transmit the contents using the USRP Sink, or you could do it live, i.e. directly stream the DVB-x signal like a TV station would. Either way, you'd still need a computer to do that – and your raspberry Pi is quite a bit too slow to sustain 30 MS/s over USB3. Simply won't happen, but any modern business laptop would do, probably, at least for the pre-calculated looping case. As you're in an industrial environment, you might prefer on of the cheaper IPC intel boards instead of a laptop, but that's in the end up to you – the benefit is that you can do the development and testing on a bog-normal PC/laptop and once everything works, put the software on a physically smaller computer.