Do you wonder why there are hardly any Seekers left? Because in his zealousness to keep the Ark secret from the Fallen Soundwave had the Seekers tracked down. Those Seekers that threaten the plan and are close to uncovering Megatron's deal with Sentinel Prime are eliminated by Soundwave. Becoming trophies. That car museum of Dylan's? Among those are Soundwave's trophy collection of dead Seekers.