However, I’m having a hard time finding a clean ISO/ROM for it. A lot of the sites I’m finding via search look super sketchy (you know the ones—pop-ups, fake download buttons, the works). I don't want to brick my PC or my Wii with malware.

The game can run at 4K 60FPS with modern hardware.

Visit the official Dolphin Emulator website and download the latest "Beta" or "Development" version (avoid old "Stable" versions as they lack modern optimizations).

If you aren't playing on original hardware, the is the standard for running the Wii ROM on PC.

Finding a secure, functional requires navigating a landscape filled with broken links and malicious files. This comprehensive guide details the game's mechanics, optimal emulation setups, and safety protocols for retro gamers. Game Overview: Transformers Prime on Nintendo Wii

If you have secured your ROM and want to experience Transformers Prime looking better than it ever did on original hardware, use these optimized Dolphin Emulator settings: Graphics Enhancements

I cannot provide a direct download, but I can help you verify a file’s integrity (e.g., matching a known good hash) or explain how to dump your own Wii disc legally. Would either of those be useful?