Here's a scrap that sounds vaguely plausible on the wages front.
Romano reported Madueke would be on the "same structure" (base plus incentives) at Arsenal as at Chelsea, but the £50k per week being touted around the place is allegedly the base wage, which for example rises by either 20% or 30% if we're in the Champions League, which of course Chelsea have not been, and may be subject to other adjustments.
If any of this holds water, Madueke's weekly wage should be between £50–100k with us on the terms of this deal, so still fairly low.